INDEX: TABLE OF SUBSTITUTION REACTIONS OF

Substrates Leaving group Entering group* PAGE ELECTROPHILIC SUBSTITUTIONS Atylation and carboxylation Pyridines H .CHO, .COPh 162 1-oxide .COMe 162 Pyridines .C02H 163 Alkylation and substituted alkylation Pyridines H . CRa, . CH2NR2 163 .C02H .C(OH)R2 163 Deuteration and tritiation Pyridinium H T 164 Pyridine 1-oxides (cations) D 164 Diazo coupling Pyridines H .N2Ar 164 Halogenation Pyridines H Cl, Br, I 164-9 Pyridine !-oxide Br 169-70 Pyridines .SOaR Cl, Br 164, 166 Hydroxylation Pyridines H .O.SOaH,.OH 170 Aietalation, halogen-metal interchange Pyridines H .HgX 171 Pyridine !-oxide .HgX 171 Pyridines Br, I Li 170-1 and nitrosation Pyridines H .N02 171--4 Pyridine !-oxides .N02 174 Pyridines .NO 176 Sulphonation Pyridines H .SOaR 176-7 Pyridine 1-oxides .SOaR 177 Thiotyanation Pyridines H .SCN 178 NUCLEOPHILIC SUBSTITUTIONS AlJilation Pyridines H .COR 200 Alkylation and substituted alkylation Pyridines H alkyl, allyl 100-3 Pyridine !-oxides .c;cH, alkyl 201,203 Pyridinium ions . C: C. C02Me, alkyl 192, 203 (.CH2COMe) 204 Pyridinium ions (acyl) alkyl, (.C;C.Ph) 201 (.CH(R) .COR'}, (.CH2N02) 205 (alkoxy} alkyl 201 (acyloxy) .CH(CN) .C02Et 206 417 TABLE INDEX Substrates Leaving group Entering group PAGE Alkylation and substituted alkylation-continued Pyridines halogen alkyl 201,203 . CH(CN)Ph, . CE<(CN)Ph'} .C(CN)Ars, .C(Me2) .COsEt, .CEt. (COsEt)s, 203 . CHAr. SOsR, .CH(COsEt)s, . CEt(C02Et)s Pyridine (via pyridyne) Br .CHsCOPh 204 Pyridine !-oxides Br .CHAr:. COsEt, .CHPh.COsEt 204 Pyridinium ions halogen alkyl 203 . CH(COPh) . COCHsR, + . CH2. CsH4NEt 205 Pyridines .OMe .CH(COsEt)2 203 Pyridones :0 :CHR 201 Pyridinium ions .OR alkyl 203 Amination and substituted amination Pyridines H .NHs, .NHPh, .NHR, .NHNHR 206--8 + Pyridinium ions :N. 186,209-10 I Pyridines .NHs .NH.Csli4N 210 + Pyridinium ions :N. .NHs, .NHPh 210 .CN .NHa 210 Pyridines halogen .NH2, .NHR, .NRa 191, 210-1, 214, 216 .NHAr, .NHNHR 211, 216 + :N. 191, 212,216 I Pyridines (via pyridynes) .NHa, .NRa 214 Pyridine 1-oxides .NH2, .NR2, .NHNHa 213, 215-6 Pyridine 1-oxides (via pyridynes) .NHa 215 Pyridinium salts .NHs, .NHR, .NHAr 213 .NHNHCOPh 213 + :~. (intramolecular) Pyridines .OH, .OAr .NH2, .NHPh 218-9 .O.COMe, + • O.SOaC7H7 :N. 219 I Pyridine 1-oxides .OAr .NHR 219 Pyridinium ions .OR, .OAr .NHR 219 Pyridines .NOa .NH2, .NHR, .NRs 212-3,219 .SOsH .NHs, .NHR 219-20 Pyridine 1-oxides .SR .NHR, .NHAr 219 Pyridinium ions .SR, .SAr .NHR 219 Arylation Pyridines H .Ar 220-3 Pyridine 1-oxides .Ar 220-3 Pyridinium ions .Ar 220,223 Pyridines Br .Ph 223 Cl .Ar(intramolecular) 223-4 Modified carbonyl reactions Pyridines H .CRaOH 224-5 418 TABLE INDEX Substrates Leaving group Entering group PAGE Formation of cyanides Pyridinium ions H (.CN) 225 (1-alkoxy) H, .OMe .CN 225--B Pyridines .N2+ .CN 226 Pyridine !-oxides .N2+ .CN 226-7 Pyridines halogen .CN 227 .SOaNa(K) .CN 227 Pyridine !-oxides .SOaNa .CN 227 Halogenation Pyridines H .Cl 227--8 Pyridinium ions H (. Cl) (followed by electrophilic bromination) 228 .Cl 228-9 + Pyridines :N. halogen 229 ' .N2+ 229-30,241,397 Pyridine 1-oxides .N2+ 230 Pyridines halogen 230 Pyridinium ions halogen 180 Pyridines .OH 231-2 Pyridine 1-oxides .OH Cl 232 Pyridines .N02 halogen 232-3 Pyridine !-oxides .N02 halogen 233 Pyridines .SOaH Cl 233

Hydroxylation and substituted hydroxylation Pyridines H .OH 234 Pyridine 1-oxides H .OAc, .O.S02C7H7 234-5 Pyridinium ions H (.O.COR) 236 H (OH) (followed by oxidation to:O) 236-8 Pyridine 1-oxides .C02H .O.COPh 238 Pyridinium ions .C02H (OH) (followed by oxidation to:O) 238 + .CH2NCsHs :0 238 Pyridines .NH2, .NHMe, .NMe2, .NHN02 .OH 238--9 + :N. .OH, .OR, .OAr 239 I Pyridinium ions . NH2, .NHMe, .NMe2, .NHN02 :0 238-9 .CN .OH 239 Pyridines .N2+ .OH, .OR, .OAr 239--41 halogen . OH, . OAc, . OR, . OAr 241-7 Pyridine 1-oxides halogen .OH, .OR, .OAr 245 Pyridinium ions .OH 245 .OAc 242,379 Pyridines .OR, .OAr .OH 247--8 Pyridine 1-oxides .OR .OH 248 Pyridinium ions .OR, .OAr .OH 248 Pyridines .N02 .OH, .OR, .OAr 248 Pyridine 1-oxides .N02 .OH, .OR, .OAr 248 Pyridinium ions .N02 .OH, .OAc 248-9 Pyridines .SH .OH 249 .SOMe, .SOaH, .SOaNa .OMe, .OH, .OR 249

Sulphur-bond formation Pyridinium ions H ( .SR), (. S02H) 249 H .SR 250 419 TABLE INDEX Substrates Leaving group Entering group PAGE + Pyridines :N. .SH, .SR, .SOaH 251 .N2+ .SH, .SCN 251 halogen .SH, .SR, .S., .SOaH 251 + .SC(NHz) :NH2 251 + Pyridine 1-oxides .SC(NHz) :NH2 251 .SOaH 251 Pyridinium ions :S 251 Pyridines .OH,:O .SH, :S 251 Pyridine 1-oxides .N02 .SR, .SOaH 251

RADICAL SUBSTITUTIONS Alkylation and substituted alkylation Pyridines H . CPha, alkyl 251-2 Arylation Pyridines H .Ar 253-5 H (intramolecular) 256 Pyridine 1-oxid~ H .Ph 253

* When the entering group is in brackets the substitution is not completed but stops at the stage of addition.

420 SUBJECT INDEX (Page numbers in italics refer to Tables.)

Acetone , 72 Acylpyrroles-continued Acylpyridines, 311-6, 312-4 N-, rearrangement to C-acylpyrroles, aldehydes, 311-5, 312-3 109 alkylation, 315 Alkenylpyridines, 122; see Stilbazoles bisulphite compounds, 311 cinnolines from, 350-1 Cannizzaro reaction, 314 dihalides, 371 hydration, 311 dehydrohalogenation, 373 reactions with electrophilic additions, 349-51 cyanide, 314 of halogen hydracids, 350 diazoalkanes, 315 of halogens, 349-50 !-oxides, 312-3 ionization constants, 146 oximes, metal complexes, 315, 397 nucleophilic additions, 351-3; see Vinyl• quaternary salts, reactions with alkali, pyridines 397 oxidation, 351 Wittig reaction, 314 reduction, 257, 266, 353 dipole moments, 124 Alkoxycarbonylpyridines, 317-9, 321-2 ionization constants, 146 Claisen reaction, 322 ketones, 313-4, 315-6 dipole moments, 124, 126 oximes, 313--4 hydrolysis, 321-2 Beckmann rearrangements, 315 and Hammett equation, 156, 322 metal complexes, 315 ionization constants, 146-7 Neher reaction, 315 !-oxides, 319 reduction, 263-4, 315 hydrolysis, 322 side chain, 314-6 reactions at with N-, see Pyridinium ions, 1-acyl alkyl halides, kinetics, 189-90 oximes, 312-4 alkylating reagents, 180 ionization constants, 146, 397 oxidizing agents, 197 tautomerism of, 154 reduction, 257-8, 263-4 reactions stretching frequencies, carbonyl groups, at nitrogen with 142 alkylating reagents, 180 ultra-violet spectra, 139 oxidizing agents, 197 Alkoxycarbonylpyrroles, 93, 95-6 with Grignard reagents, 220 acylization, 95-96 stretching frequencies of carbonyl groups, hydrolysis, 95 142 kinetics, 110 ultra-violet spectra, 129 N-H stretching frequencies; rotational Acylpyrroles, isomerism, I 09 C-, 92-4, 93 ultra-violet spectra, 55 acidity, 62 Alkylpyridines, 121-2 acyl-group displacement in acidity, 324-31 halogenation, 78 and nitration, 80 alkylation, 325 aldehydes, 93 hydrogen exchange, 325-6 preparation by metalation, 325 Gattermann reaction, 63-4 tautomerism, 324-5 Reimer-Tiemann reaction, 63 molecular orbital theory, 330 hydrogen bonding in, 58 N-alkyl, see Pyridinium ions, !-alkyl oximes, in Beckmann rearrangement, 99 alkylation, nucleophilic, 202 preparation by amination, nucleophilic, 206-7 Roesch reaction, 64 deuteration and tritiation, Vilsmeier reaction, 64 nuclear, electrophilic, 164 salts, 61 dipole moments, 123-5 stretching frequencies, , halogenation, electrophilic, 58 nuclear, 165, 168, 279 ultra-violet spectra, 55 effect of aluminium chloride, 166-8 Wittig reactions with, 110 side chain, 165 421 SUBJECT INDEX Alkylpyridines-continued Alkylpyridines, side-chain reactions-continued heats of reaction, with amination, 210, 333 Lewis , 151 base-catalysed, see metallic derivatives methanesulphonic , 151 dehydrogenation, 348 infra-red spectra, 141 diazo coupling, 339 ionization constants, 145-6, 150-1 halogenation, 165, 339-40, 345 isomerization, thermal, 324 hydrogen exchange, 325-7, 397 mercuration, 171 Mannich, 332 metallic derivatives, see Grignard re• metalation, 202, 207, 220-1, 325, 327-8 agents, Lithium, etc. metals nitration, 343 nitration, 171-2 nitrosation, 343 1-oxides, oxidation, 346-8, 397 deuteration, nuclear, 164 Willgerodt, 348 reactions with with acetic anhydride, 234, 245, 281, acrylonitrile, 332-3 340-3 aldehydes, 334-8 aldehydes, 336 amines, 343 arenesulphonyl chlorides, 210, 340 benzenesulphonyl chloride, 344 arylacetic acid anhydrides, 380 ketones, 334, 339 carboxylic acid chlorides, 343 radicals, 344-5 ketene, 343 ultra-violet spectra, 127-9 side-chain reactions, and tautomerism, 137 halogenation, 165 Alkylpyrroles, hydrogen exchange, 326, 397 C-, 52-3 sulphonation, 177 dipyrrylmethenes formed by bromina- quaternary salts (1-alkoxy), tion, 78 acidity, 328 ionization constants, 60 pyridone methides from, 328-30 metallic derivatives, 61 reactions with methyl groups in, alkali, 236, 238, 328-30 acetoxymethylation, 97 mercaptides, 250 bromination 77-8, 96, 102 side-chain reactions, chlorination (sulphuryl chloride), 78, arylation (cyanine formation), 333-4 96-7, 102 with displacement of, in nitration, 80 aldehydes, 336-7 phenylation, 97 arnines, 343-4 oxidation to ketones, 337-9 fatty acids, 97 Schiff bases, 336 maleimides, 87, 96 ozonization, 265 rearrangement by aluminium chloride, photochromotropism, 345 68 polarography, 324 salts, 61 reactions ultra-violet spectra, 54 at nitrogen, N-, rearrangement to C-, 109 oxidation, 197 Alkynylpyridines, 122; see Tolazoles with hydration, 350 acylating agents, 195 hydrogenation, 348 alkyl halides, kinetics, 188-90 ionization constants, 146 alkylating reagents, 180-1 nucleophilic additions of aryl halides, kinetics, 191 malonic , 352 arylating agents, 185 alkoxides, 352 with Alternant hydrocarbons, ethyl bromide, 328 non-bonding molecular orbital method, lithium alkyls, 202, 327 43 ff. lithium aryls, 220-2, 327 1r-electron distribution, 39 potassamide, 327 substitution into, 39, 43 ff. sodarnide, 206-7, 327 Aminocarbonylpyridines, 317-9, 321 thionyl chloride, 186 arnination, nucleophilic, 206-7 salts, cf. metallic derivatives dipole moments, 124 cadmium, 328 Hofmann reaction, 321, 323 lithium, 327 ionization constants, 147 magnesium, 328 reactions at ring nitrogen, mercuric, 328 oxidation, 197-8 potassium, 327 with alkylating reagents, 180 sodium, 327 reduction, 264, 321 side-chain reactions, Aminopyridines, 354-60, 35~7 acylation, 331-2 acyl derivatives, Madelung synthesis, alkylation (incl. substituted), 325,332-3 383-4 422 SUBJECT INDEX Aminopyridines-conlinued Aminopyridines, reactions with-continued arylation, nucleophilic, 221-2 sulphonylating agents, 196 cations, 138, IS3, 279 urea and thiourea, 3S4 complexes with halogens, 162, 168 reduction, 2S7, 263 diazo coupling, 164 sulphonation, 177 diazo oxides from, 270, 3S9 tautomerism, 137-8, 143, 1S3-S, 154 diazotization, 176, 226, 229-30, 239-41, thiocyanation, 178 3S9 ultra-violet spectra, 129-30, 137-8, 278 dipole moments, 124, 126 and halogenation, electrophilic, 168-9, 279 steric inhibition of resonance, 138 hydrolysis, tautomerism, 137 acid, 239 Aminopyrroles, 97-9, 98 alkaline, 238-9 acylation, 97-9 hydroxylation, electrophilic, 170 benzal derivatives, 99 infra-red spectra, 143 diazotization, 97-100 and tautomerism, 143 oxidation, 99 ionization constants, 147, 279 tautomerism, 98-9 and ureas from, 99 Hammett equation, IS7-9 urethanes related to, 97 steric inhibition of resonance, 1S3, Aralkylpyridines, ISS-9 nitration, 176 tautomerism, IS3-S of !-oxides, 176 mercuration, 171 Aromatic metal salts, alkylation, 182 reactivity, naphthyridines from, 198-9 localization energies and, 42 nitration, 172-3 theory of, 8 ni trosation, isolated molecule, 33-4, 37, 46 nuclear, 176 and free valency, 37 side-chain, 176, 3S9 molecular orbital treatment, 34 ff. nuclear magnetic resonance spectra, 279 transition state, 41 ff. oxidation, to valence-bond method and, 47 azo and azoxy compounds, 3S9 Wheland transition state and, 41 nitropyridines, 198, 3S9-{)0, 397 sextet, in !-oxides, 357 benzene, 4, 17 diazotization, 226-7, 3S9, 361 indole, 7 ionization constants, 149 pyridine, 7, 17 reactions with pyrrole, 7, 17 benzoyl chloride, 229 quinoline, 7 phosgene, 3S4 stability, theory of, 8, 14 tautomerism, 140, 144, ISS structure, ultra-violet spectra, 133, 140 description of, photo-dimerization, 264 molecular orbital, 22-4 quaternary salts, valence bond, 13-S Dimroth rearrangement, 182, 269 theory of, 8, 13, 22 reactions with alkali, 238-9 Arylazoaminopyridines, 164 reactions Arylazopyridines, see Azopyridines at ring nitrogen, Arylhydrazinopyridines, 362 oxidation, 197-8 reactions, 360 with !-oxides, 362 acylating agents, 196 reactions, 360 aldehydes, 3S8-9 Arylpyridines, 122 reductive alkylation, 3S9 dipole moments, 124, 278 alkali, 238-9 hydrogenation, 263 alkylating reagents, 180-2 ionization constants, 147-8 aryl ethers and halides, 3S4, 3S8 nitration, 17S benzoquinone, 194 non-planarity, 127, 136, 278, 36S cx-bromacrylic acid, 192 oxidation, 26S carbon disJlphide, 3S4 !-oxides, and isocyanates, 3S4 ionization constants, 149 ethyl chloroformate, 3S4 nitration, 17S ketones, 3S9 reactions at nitrogen with methyl propiolate, 192 alkylating agents, 180 naphthols, 3S8 oxidizing agents, 197 nitroso compounds, 3S8 ultra-violet spectra, 130, 136, 278 nitrous acid, 3S9 Arylpyrroles, phosgene, 3S4 C-, 53 phosphorus trichloride, 3S8 nitration and nitrosation, 80 423 SUBJECT INDEX Arylpyrroles, C--continued Cadmium dipicolyl, reactions with , ultra-violet spectra, 56 380 N-, rearrangement to C-, 109 Canonical structures, 14 Atom (-atom,-bond) polarizability, see of Molecular orbital method benzene, 14 Auxiliary inductive parameters, see Molecu• polynuclear compounds, I 4-5 lar orbital method pyridine, I 5 Azopyridines, 363 pyrrole, 16-7 cis-trans-isomerism. 365 Conjugative mechanism, I 0 dipole moments, 278 Coulomb integrals, see Molecular orbital ionization constants, 148 method N-oxidation, 197-8 Covalent bonds, 11-2 !-oxides, 364 Cyanines, 205, 267-8, 333-4 cis-trans isomerism, 365 Cyanopyridines, 366-8 reactions with hydrochloric acid, 362 dipole moments, 124---B reactions with from pyridine I -oxides, 225---B diazoalkanes, 362-3 hydrolysis, 366-7 Grignard reagents, 362-3 infra-red spectra, 142 hydrochloric acid, 362 ionization constants, 148 reduction, 364 oxidation, 367 4,4' -trans-, 1, 1'-dioxide, 364 polarography, 368 molecular dimensions, 120 quaternary salts, reactions with Azopyrroles, 98 alkali, 239 acidity and basicity, 99 ammonia, 210 reduction, 98-9 reactions stability, 99 at ring nitrogen, with Azoxypyridines, 363 alkylating reagents, I80 !-oxides, 364 oxidizing agents, 197-8 reduction, 364-5 with Grignard reagents, 200 reduction, 364 reduction, 367-8 ultra-violet spectra, 128, 130-1 Benzene, Cyanopyrroles, ultra-violet spectra, 56 early structures, 3--4 energies of delocalization, 25-6 Delocalization energy, 25-6, 27 localization, for, 42 of resonance, benzene, 25-6 empirical, 18-9, 26 nitrogen heteroaromatics, 26 vertical, 17, 25-6, 27 pyridine and pyrrole, 26 free valency in, 38 Deuteropyridines, infra-red spectra, 141 geometry, 14-5 Deuteropyrroles, 75 mesomerism, 13--4 infra-red spectra, 57 resonance in, 13--4 Diazopyrroles, 98, 100 stability, 14 from nitrosopyrro1es, 80 wave function, 13--4 Diphosphopyridine nucleotide, Benzylpyridines, 122 reactions with oxidation, 265, 346 cyanide ions, 225 photochromotropism, 345 enolate anions, 204 Bipyridyls, 122 , 209 complexes with metals, 159---BO sodium bisulphite and , 249 from pyridyl radicals, 395---B , 249 ionization constants, 147-8 reduction, optical resolution, 365 enzymatic, 259---BO Bond with sodium dithionite, 259---BO angle, in Dipyrrylmethanes, from and alde• nitrogen heterocycles, 30 hydes, 71-2 pyridine, 15 Double bonds, 13 derivatives, 120 pyrrole, 16 energies, 20-1 le~gths, 27-9, 30 Ehrlich's reaction, see Pyrroles, reactions m with p-dimethylaminobenzaldehyde pyridine, 15 Electromeric effect, 10 derivatives, 120 pyrrole, 16 relation to bond order, 28 Free valency, 37-8, 39 order, 27-9, 30, 37 Frontier electron densities, 37 424 SUBJECT INDEX Gattermann reaction, with pyrroles, 63-4 Halogenopyridines, reactions with-continued Glutacondialdehyde, derivatives by pyri• alkoxides, kinetics, 245-7 dine ring opening, 266-9 amines, 211-3 Grignard reagents, acid , 215 picolyl, reactions with kinetics, 191, 215-8 acetyl chloride, 379 ammonia, 210-3, 280 alkyl halides, 381 cuprous cyanide, 227 pyridyl, reactions with enolate anions, 203 acetic anhydride, 380 Grignard reagents, 201, 371 aldehydes and ketones, 382-3 hydrazines, 211 allyl halides, 381 hydrosulphides, 251 arsenic compounds, 383 lithium alkyls, 170, 203 benzamide, 380 mercaptides, 251 carbon dioxide, 381 metal amides, 211, 214, 280-1 esters, 379 pyridine, 184 ethyl orthoformate, 380 silver benzoate, 241-2 lead compounds, 383 sodium acetate, 241-2 nitriles, 379 sodium sulphide and sulphite, 251 phosphorus compounds, 383 thiourea, 251 reduction, 264, 371, 384 side chain, 371 Halogenopyridines, 368-71 reactions with nucleophiles, 373 auto-quaternization, 184 sulphonation, 177 dipole moments, 123-5 ultra-violet spectra, 128, 12 8, 131, 136 halogen Halogenopyrroles, 101 exchange in, 180,230,280 acidity, 62, 100 -lithium exchange, 170-1, 223 bromine replaced by alkoxyl, I 04 migration in, 371-2 dehalogenation, hydrolysis, by hydriodic acid, 101 acid-catalysed, 241-2 reductive, 100 alkaline, 241-2 displacement from in Ullmann syntheses, 372 halogens, in diazo coupling, 77 infra-red spectra, 141 iodine, in nitration, 80 ionization constants, 148, 279 exchange of halogens in, 78, 101-2 nitration, 173, 279 in Ullmann reaction, 101 nuclear quadrupole resonance spectra, 145 n.m.r. spectra, 59 !-oxides, 370 protodehalogenation, 101 reactions with reactions with nucleophiles, 110 alkoxides, kinetics, 245-7, 280 absence of, 101 amines, 213, 280 stability, 100 kinetics, 216-7 Hammett equation, 47 enolate anions, 204 and hydrazine, 213 alkoxylation of halogenopyridines, 247 metal amides, 215, 281 amination of halogenopyridines, 217 potassium thiocyanate, 251 hydrolysis of alkoxycarbonylpyridines, polarography, 371 156,322 quaternary salts, infra-red spectra, pyridines, pyridine!• halogen exchange in, 180 oxides, 142 hydrolysis, 245 ionization of reactions with pyridine 1-oxides, 156-8 alkoxides and aryloxides, kinetics, pyridines, 153, 155-9, 279 245-7 nuclear quadrupole resonance spectra, carboxylic acids, 242 145 enolate anions, 205 N -oxidation of pyridines, 197 metal alkyls, 203 quaternization of pyridines, 187, 280 picolinium salts, 205 reactivity of pyridine (1-oxide), 277 potassium hydrosulphide, 251 tautomerism of pyridines, 153 pyridynes from, 204, 214 substituent constants of, reactions and pyridine reactivity, 271 at nitrogen with for pyridine oxide function and pyri• alkylating agents, 180 dinic nitrogen, 156,247 alkyl halides, kinetics, 189, 190 Heats of combustion, and empirical reso• oxidizing agents, 197 nance energies, 18--21 with Hoesch reaction, with pyrroles, 66 acetic anhydride, 245 Hybridization, 12-6 alkoxides and aryloxides, 242-7, 243- vertical resonance energy and, 27 4 Hydroxylaminopyridines, 385-6 425 SUBJECT INDEX Hydroxypyridines, 374-7 Hydroxypyridines, 0-aryl---continued amination, nucleophilic, 206-7 quaternary salts, C-alkyl, dipotassium derivatives, alkyla- amination, 219 tion, 397 hydrolysis, 248 carboxylation, I63 thermal isomerization, 378 cations, structure, I44-5 oxidation, 373 diazo coupling, 164 1-oxides, 376-7 dipole moments, 125, 278 cations, structure, 145 halogenation, electrophilic, I69, 37I-2 ionization constants, 149 hydrogen exchange, acid-catalysed, 279- nuclear magnetic resonance spectra, 145 80 reactions with phosphoryl chloride, 232 hydroxylation, electrophilic, 170 tautomerism, 140, 144-5, 155 infra-red spectra, 144 ultra-violet spectra, 133, 140 and tautomerism, I43-4 reactions, ionization constants, 148, 279 at nitrogen with oxidizing agents, and tautomerism, 153-5 197 mcrcuration, I71 with metal salts, acrylonitrile, 192 alkylation, I83 acylating agents, 196 reactions with alkylating agents, 180, 183 halogenopyridines, 184 ammonia, 218 iodobenzene, I84 oc-bromacrylic acid, 192 nitration, 173-4, 279--80 di-(trifluoromethyl) acetylene, 280 nitrosation, 176 ferric chloride, 373, 377 nuclear magnetic resonance spectra, 145 Folin-Denis reagent, 373, 377 and tautomerism, 145 phosphorus halides, 231-2 0-acyl, 374-7 phosphorus pentasulphide, 251 acylating properties, 379 sulphonylating agents, 196 autoquaternization, 185, 219 reduction, 257--8, 264, 373, 378 hydrogenolysis, 264, 379. sulphonation, 177 hydrolysis, 379 tautomerism, 139, 143, 145, 153-5, 154 reduction, 264 ultra-violet spectra, 131, 139, 278 0-alkyl, 374-7 and tautomerism, 139 arylation, nucleophilic, 221-2 Hydroxypyrroles, 104 cations, structure, I 44-5 acetylation, 64, 104-5 dipole moments, 125 coupling with diazonium salts, I04 hydrolysis, 247--8 forming of benzylidene derivatives, 104-5 infra-red spectra, 144 methylation, 104-5 ionization constants, 148 nitrosation, 104 N-oxidation, 197 0-ethylation, 105 nitration, I 73-4, 279--80 reactions with ferric ions, 104 1-oxides, 376-7 spectroscopy, hydrolysis, 248 n.m.r., 111 ionization constants, 149 ultra-violet, and tautomerism, 105 reactions with acylating agents, 397 tautomerism, 104-5, Ill thermal isomerization, 379 quaternary salts, hydrolysis, 248 Imidazole, Bamberger's structure, 6 reactions with Inductive effect, 11 amines, 219 Iodopyridines, dichlorides, 372-3 metal alkyls, 203 Iodopyrroles, 101 reactions with iodine displacement from, by alkylating agents, 183 formaldehyde, 73 alkyl halides, kinetics, 189-90 hydriodic acid, 75 ammonia, 213, 218 Isolated molecule theory, see Aromatic sulphonation, 177 reactivity thermal isomerization, 378 Isoquinoline, ultra-violet spectra, 131, 139 non-bonding molecular orbital method 0-allyl, Claisen rearrangement, 378-9 and substitution into, 45 0-arenesulphonyl, 374 w-electron densities in, 36 autoquaternization, 185 hydrogenolysis, 264, 379 reduction, 264 Lithium picolyls and homologues, 0-aryl, 374-7 reactions with amination, %18-9 acid anhydrides and halides, 380 hydrolysis, 247 aldehydes and ketones, 382-3 1-oxides, amination, 219 oxides, 383 426 SUBJECT INDEX Lithium picolyls and homologues, reactions Nitropyridines--continued with-continued ionization constants, 148 alkyl halides, 381, 383 and arsenic compounds, 383 Hammett equation, 159 bromine, 383 steric inhibition of resonance, 159 carbon dioxide, 381 1-oxides, 385 esters, 380-1, 383 ionization constants, 149 nitriles, 380, 383 reactions with Lithium acetic anhydride, 248 pyridyls, acetyl halides, 233 from halogenopyridines, 170-1 alcohols and , 248 reactions with alkoxides and aryloxides, 248 acid anhydrides, 380 ammonia, 219 carbon dioxide, 381 halogen hydracids, 233 esters, 380 mercaptides, 251 ethyl pyridinecarboxylates, 380 phosphorus halides, 233 ketones, 383 sodium sulphite, 251 nitriles, 380 sulphuryl chloride, 233 pyrrole(s), 61 reduction, 384-6 reactions with quaternary salts, hydrolysis, 248 allylic halides, 67-8 reactions ethoxycarbonyl chloride, 66 at ring nitrogen with phosphoryl chloride, 111 alkylating agents, 180 Localization energies, 42 oxidizing agents, 197 with acetic anhydride, 248 Mesomeric effect, 10 alkali, 248 Mesomerism, 10 alkoxides and aryloxides, 248 1-Methylpyrrole, n.m.r. spectrum; associ• amines, 219 ation, 109 ammonia, 212-3, 219 halogen Molecular orbital method, 22 ff. hydracids, 232-3, 248 atom-atom (-bond) polarizability in, 39 phosphoryl chloride, 233 auxiliary inductive parameters in, 34-6, reduction, 227, 384--6 40 ultra-violet spectra, 132 and Coulomb integrals, 23 steric inhibition of resonance, 136 for Nitropyrroles, 108-9 heteroatoms, 24, 34 acidity, 62, 108-9 nitrogen, 34-6, 37, 40 alkylation, 109 Hucke! approximation, 24 from nitrosopyrroles (oxidation), 80 integrals in, reduction to aminopyrroles, 99 overlap, 24 sodium salts of, 62 tautomerism, use with heterocyclic compounds, 38 109 resonance, 23, 35 ultra-violet spectra, 56 Nitrosaminopyridines, non-bonding, see Alternant hydrocarbons 359, 361, 363 secular equations, 23 N-acyl, 359, 361, 363 self-polarizability in, 39 pyridyl radicals from, 395 Nitrosopyridines, 385-6 Nitrosopyrroles, 107-8 acid hydrolysis (ring opening), 88 Nitraminopyridines, 360-1, 363 acidity, 62, 107-8 alkylation, 182 conversion into diazopyrroles, 80 hydrolysis, 239 oxidation to nitropyrroles, 80 infra-red spectra, 143 pyriJ;Uidines from, 89 quaternary salts, reactions with alkali, reduction to aminopyrroles, 97, 99 238-9 salts, 61 rearrangement, acid-catalysed, 172-3, 279 sodium, 62 tautomerism, 138, 143 tautomerism, 63, 107-8 ultra-violet spectra, 138 Non-crossing rule, 46 4-Nitropyridine 1-oxide, molecular dimen• sions, 120 Nitropyridines, 385 Overlap integrals, see Molecular orbital autoquaternization, 185 method dipole moments, 125-6 hydrolysis, acid-catalysed, 248 alkaline, 248 Phenacylpyridines, 314 infra-red spectra, 142 oximes, 314 and steric inhibition of resonance, 142 Beckmann rearrangement, 315 427 SUBJECT INDEX Phenacylpyridines-continued Pyridine, complexes with non-metals-contd. tautomerism, 315 sulphur dioxide and trioxide, 162 and infra-red spectra, 279 reaction with alkali, 268 and ionization constants, 279 thionyl chloride, 162, 186, 228 Picolinic acid hydrochloride, molecular diazo oxides, ring contraction, 270 dimensions, 278 -dicarboxylic acids, 318, 323--4 7t-Electron densities, 34, 37, 39 -diazonium salts, and polarizability (atom-atom, atom• coupling reactions, 361, 397 bond, self-), 39 cyanopyridines from, 226 Polarizability, 10, 33 halogenopyridines from, 229-30, 397 and molecular orbital theory, 38 hydroxypyridines from, 239--41 pyridyls ether irom, 241 Polarization, 10 pyridyl radicals from, 361 Polypyridyls, 122 reduction, 361 complexes with metals, 160 !-oxides, Porphyrins, from pyrroles and carbonyl coupling reactions, 361 Potassium compounds, 12 cyanopyridines from, 226-7 picolyls (and homologues), halogenopyridine !-oxides from, 230 !-oxides, reactions with delocalization energy, 26 aldehydes, 383 dipole moment, 16, 124, 126, 278 esters, 380 and molecular orbital parameters, 35, reactions with 126, 278 alkyl halides, 382 early structures, 5-7 esters, 380-1 electrophilic substitution into and pyrrole(s), 61 localization energies, 42 alkylation, 66 Tt"-electron densities, 35 reactions with empirical resonance energy, 19, 21, 26 allylic halides, 67-8 esters, see Alkoxycarbonylpyridines ethoxycarbonyl chloride, 66 free valency in, 38 Pyridils, 314, 316 geometry, 16, 29 Pyridine, 121 heat of reaction, with -acetic acids, 318-9 Lewis acids, 151 decarboxylation, 320-1 methanesulphonic acid, 151 basicity, 16, 145 hydrochloride, molecular dimensions, 120 -carboxylic acids, 316-24, 317-9 infra-red spectrum, 141, 279 alkylation, I 82 ionization constants, 146 amides, see Aminocarbonylpyr• isolation, 4 idines localization energie~, 42, 276 betaines, 139, 182 mercuration, 171 ionization constants, 146 metallic derivatives, see Grignard re• chlorides, 317, 322-3 agents, Lithium, etc. complexes with metals, 316 molecular decarboxylation, 316, 319-21 dimensions, 15 dipole moments, 124 orbital description, 33--4 halogenation, 168 nuclear magnetic resonance spectra, 144- Hammick reaction, 163, 319 5 hydrazides, 321 nucleus, reactivity, 270-8 ionization constants, 146 and N-oxidation, 197 free valencies, 278 !-oxides, 319 localization energies, 42, 275-7 ionization constants, 149 mesomerism, 273 metal complexes, 316 non-bonding m.o. theory, 273 reactions with diphenyldiazomethane, Tt"-electron densities, 213-5 321 Dewar's treatment, 277-8 reactions with to diphenyldiazo!nethane, 321 , 270-1 thionyl chloride, 227-8 nucleophiles, 271-3 reduction, 257-8, 263--4, 321 radicals, 273 complexes with I -oxide, metals, 159---00 dipole moment, 125---B phenylation, radical, 255 ionization constant, 149 non-metals, 160-2 mercuration, 171 dinitrogen pentoxide, 162 phenylation, halogens, 160-2, 161 nucleophilic, 281 nitronium fluoborate, 162, 279 radical, 253 nitrosonium fluoborate, 279 quaternary salts, reactions with alkali, phosphorus pentachloride, 162 388 428 SUBJECT INDEX Pyridine !-oxide--continued Pyridine, reactions with--continued reactions with Grignard reagents, 200, 220 acetic anhydride and bromine, 234- iodine monochloride, 168, 186 5,281 lead tetra-alkanecarboxylates, 252 arylacetic acid anhydrides, 380 lithium benzoic anhydride, 234 alkyls, 202 2-bromopyridine, 210 aluminium hydride, 258 Grignard reagents, 201, 281 aryls, 220-2 lithium phenyl, 222 methanol, 252, 396 mercaptides, 250 methyl cyanoacetate, 205 p-nitrobenzoyl nitrate, 235 nitromethane and benzoyl chloride, phosphorus chlorides, 228 205 sodium acetylide, 203 phenyl calcium iodide, 222-3 sulphuryl chloride, 228 potassium, 396 p-toluenesulphonyl chloride, 235 alkyls, 203 reactivity , 234 and Raney nickels, 396 localization energies, 275-7 sodium, 395~ mesomerism, 274 alkyls, 203 rc-electron densities, 274-5 bisulphite, 249, 264, 269 to electrophiles and nucleophiles, hydrazide, 208 271-2 thionyl chloride, 18~ substitution reactions, see pp. 417-20 trimethylsilane, 281 ultra-violet spectra, 132, 139-40 zinc-acetic anhydride, 263 ozonization, 265 reduction, 257--S, 263-4, 281 phenylation and molecular orbital para• resemblance to nitrobenzene, 33 meters, 35 resonance in, 15~ rc-electron densities, 35-6, 274 in , 123 reactions substitution at nitrogen with into, acylating agents, 195 non-bonding molecular orbital theory, alkyl halides, kinetics, 186-90, 280 44~ alkylating reagents, 178-9, 184, 280 nucleophilic and radical, localization arenesulphonylazides, 198 energies, 42 aryl halides, kinetics, 190-1 reactions, see pp. 417-20 arylating reagents, 184~ sulphonation, 176-7 bromide, 198 mercuric ions in, 160 dimethyl acetylenedicarboxylate, -sulphonic acids, 392-3, 394 193-4 alkylation, 184 divinyl sulphone, 195 autoquaternization, 220 halohydrins, 179, 192 hydrolysis, 249 ketenes, 196, 280 ionization constants, 148 maleic acid, 192 !-oxides, reactions with cyanides, 227 methyl propiolate, 192 reactions with p-nitroanisole, 280 amines and ammonia, 219-20 p-nitrophenyl phosphate, 280 cyanides, 227 olefins (oxides) and halogens, 192 phosphorus pentachloride, 233 oxidizing agents, 197 ultra-violet spectra, 131 phosphoramidate, 280 tautomerism, 139, 153-4 potassium hydroxylamine 0-sulpho- thiols, 392 nate, 198 cations, 279 ~-propiolactone, 192 dipole moments, 125, 278 quinones, 194-5 infra-red spectra, 143-4 sulphonylating agents, 195 and tautomerism, 143-4 ~-sultones, 192 ionization constants, 148 tetracyanoethylene oxide, 280 and tautomerism, 153-5 with n.m.r. spectroscopy, 279 acenaphthenone and acetic anhydride, !-oxides, ionization constants, 149 205 reactions with acetophenone and benzoyl chloride, acylating agents, 393-4 205 alkylating reagents, 183 alkanocarboxylic acids (electrolysis), oxidizing agents, 249, 391 252 tautomerism, 139, 143-4, 153-5, 154 benzoylazotriphenylmethane, 251-2 ultra-violet spectra, 131-2, 139 cyanogen bromide, 198 and tautomerism, 139 diacyl peroxides, 252 S-alkyl, 392 diazomethane, 198 alkylation, 184 429 SUBJECT INDEX Pyridine thiols, S-alkyl-continued Pyridines, !-oxides-continued ionization constants, 148 reduction, 384-6 oxidation, 198, 391, 393 Reissert compounds from, 226 1-oxides, reactions with amines, 219 ultra-violet spectra, 132-3, 139-40 quaternary salts, quaternary salts, see Pyridinium ions hydrolysis, 249 reactions reactions with amines, 219 at nitrogen with reduction, 394 acylating agents, 195-6 ultra-violet spectra, 131-2, 139 alkyl halides, kinetics, 186-90 S-aryl, alkylating reagents, 178-84, 186-90 oxidation, 391, 393 arylating reagents, 184-6, 189-91 1-oxides and quaternary salts, reac• cyanogen bromide, 198, 281 tions with amines, 219 dimethyl acetylenedicarboxylate, ultra-violet spectra, 127-9, 139, 278 193-4,280 Pyridines, oxidizing agents, 197-8 additions to, 257-64 perbenzoic acid, kinetics, 197 carbonyl reactions, potassium hydroxylamine 0-sul- electrophilic (Hammick reaction), 163 phonate, 198 nucleophilic, 224-5 quinones, 194-5 complexes with sulphonylating agents, 195-6 metals, 159-60 with infra-red spectra, 141 cyanogen bromide, 198 non-metals, 160-2 diazoalkanes, 198, 280 halogens, 169-2, 161, 279 dichlorocarbene, 269 dipole moments, 124-5, 278 Grignard reagents, 200-2, 220 disruption lithium alkyls, 203 by irradiation, 264-5 lithium aryls, 220-2 oxidative, 265 potassium hydroxide, 234 reductive, 265 Raney nickels, 396 thermal, 264-5 sodamide, 206-8 ultrasonic, 265 thionyl chloride, 227-8 electron densities in, 145 substitution reactions, see pp. 417 hydroxyalkylation by ketones, 224-5 et seq. infra-red spectra, 141-4, 279 reduction and Hammett relationship, 142 electrochemical, 257-8, 263, 281 and tautomerism, 142-4 enzymatic, 259-BO · ionization constants, 145-59, 146-9, 279, with 397 alcohols and sodium, 257 and Hammett's aluminium, ether, 258 acidity function, 279 chromous acetate, 258-9 equation, 153, 155-9 formate-formic acid, 262-3 and tautomerism, 152-5 lithium aluminium hydride, 258, 261 of excited states, 279 magnesium, 258 mercuration, 171 sodium metallic derivatives, see Grignard re• amalgam, 258-9 agents, Lithium, etc. , 261-2, 281 molecular dimensions, 15, 120, 278 dithionite, 259-61 nuclear magnetic resonance spectra, z•nc 144-5, 279, 282-3 -acetic anhydride, 263 14N-nuclear quadrupole resonance, 145 alkali, 259 1-oxides, 387 -copper couple, 258 deoxygenation, 386-8 Reissert compounds from, 225-6 0-alkyl; see Pyridinium ions, 1-alkoxy ring dipole moments, 128 contractions, 270 electron densities in, 145 openings, see Pyridinium ions infra-red spectra, 142-4, 279 substitutions into, ionization, and Hammett's acidity and tautomerism, 136-9, 278-9 function, 279 electrophilic, 162-200 constants, 149 intramolecular, 198-9 of excited states, 279 nucleophilic, 200-51 nuclear magnetic resonance spectra, 145 radical, 251-6 reactions with ultra-violet spectra, 127-41, 129-34, 278 acetic anhydride, 234-5 Pyridinium ions, phosphites, 388 1-acetoxyl-2-methyl picrate, 342 phosphorus chlorides, 228, 387-8 1-acyl, sulphuryl chloride, 228, 233 0-acylation of ketones with, 206, 223 p-toluenesulphonyl chloride, 235 arylation, nucleophilic, 223, 281 430 SUBJECT INDEX Pyridinium ions-continued Pyridinium ions-continued carboxylic acid anhydrides from, 235-6 quaternary, esterification of charge-transfer complexes, 140, 249, 273 alcohols with, 206 dequaternization by nucleophiles, 265- phenols with, 206, 223 9, 389-90 reactions with nucleophilic substitution, 272 enolate anions, 205 pyrolysis, 388-9 Grignard reagents, 201-2 reactions with 1-acyloxy, reaction with ethyl cyanoace• sodium bisulphite, 249 tate, 206 sodium dithionite, 249, 259--B1 1-alkoxy, reactions with thiols, 249 amines, 209 ring opening, nucleophilic, 265-9 bases, 209, 282 thermal isomerization (Ladenburg re• cyanide ions, 225-6 arrangement), 388-9 Grignard reagents, 20 1 reactions with mercaptides, 250 cyanide ions, 225, 281 1-alkyl, diazoalkanes, 280 alkyl group reactions with aldehydes, salts, infra-red spectra, 141-2 337-8 substitution reactions, see pp. 417-20 hydrogen exchange, 326 1-toluenesulphonyloxy, alkylating prop!"rties, 389 reaction with pyridine, 186, 209-10 bt:taines from, 329-30 rearrangement, 235 deuteration, base-catalysed, 164, 379 1-2,4,6-trinitrophenyl, reactions with ani• electrolytic oxidation, 238 line, 269 equilibrium with pseudo-bases, 236 !-vinyl, 350 iodides, colour, 140-1 polymerization, 353 nitration, 171, 279 Pyridoins, 316 reactions with