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525 Index a alcohol racemization 356, 357 acetophenone 50–53, 293, 344, 348, 443 alkali metals 398 acetoxycyclization, of 1,6-enyne 76 alkaline earth metals 398 acetylacetone 48 N-alkenyl-substituted N,S-HC ligands 349 A3 coupling reactions 231, 232 3-alkyl-3-aryloxindoles 58 acrylonitriles 69, 211, 212, 310, 348 alkyl bis(trimethylsilyloxy) methyl silanes 122 activation period 123–125 – Tamao-Kumada oxidation of 122 active species 123 2-alkylpyrrolidyl-derived formamidinium acyclic alkane 62 precursors 516 acyclic aminocarbenes 499 alkyl silyl-fluorides 209 – ligands 503 alkyl-substituted esters 210 – metalation routes 500 N-alkyl substituted NHC class 119 acyclic aminocarbene species 499 alkynes acyclic carbene chemistry 500, 516–520 – boration of 225 acyclic carbene complexes – borocarboxylation 233, 234 – in Suzuki–Miyaura crosscoupling 505 – hydrocarboxylation 234, 235 acyclic carbene–metal complexes 505 – metal-catalyzed hydrosilylation of 132 acyclic carbenes – semihydrogenation 232, 233 – characteristic feature of 503 allenes 77 – donor abilities 502 – synthesis, mechanisms 203 – ligands 502 3-allyl-3-aryl oxindoles 60 –– decomposition routes 504 allylbenzene 345 –– donor ability 502, 503 – cross-metathesis (CM) reactions of –– metalation routes of 500 510 –– structural properties 503 allylic alkylations 509 – stabilized, by lateral enamines 518 allylic benzimidate acyclic carbone ligand 519 – aza-Claisen rearrangement of 514 – in gold-catalyzed rearrangements 520 allylic substitution 220 acyclic diaminocarbenes (ADCs) 4, 5, 499 – reactions 361–363 – Alder-type 510 COPYRIGHTED– by in situ MATERIALgenerated Ru–NHC – complexes 501 complexes 362 – ligands, conformational flexibility of 503 3-allyl oxindole 60 acyclic ketones 69 aluminum reagents ADCs. See acyclic diaminocarbenes (ADCs) – conjugated addition using 209 aerosolized water 155 amide formation 355 Ag–NHC species 207 – proposed mechanism 354 AgNO3, bactericidal activity 153 amidine ligand 504 Albrecht’s group 347 amidinium-derived chiral ADC ligands alcohol oxidation 384 – enantioselective catalysis with 517 N-Heterocyclic Carbenes: Effective Tools for Organometallic Synthesis, First Edition. Edited by Steven P. Nolan. 2014 Wiley-VCH Verlag GmbH & Co. KGaA. Published 2014 by Wiley-VCH Verlag GmbH & Co. KGaA. 526 Index amidinium precursors – superparamagnetic Fe3O4-supported – chiral ADC ligands derived from 516 NHC-based catalyst amido NHC complex 400 –– for enantioselective allylation 64 amino acid complexes 184 asymmetric conjugated addition 207 aminocarbenes 4 asymmetric cross-metathesis (ACM) ampicilin 175 processes 42 anisotropies 4 asymmetric diamination 62 antibacterial activity 154 – of alkenes 63 antibacterial agents, cationic complexes asymmetric hydrogenation 44 study 174 – aromatic/heteroaromatic compounds 45 anticancer NHC–Pd Complexes 106 asymmetric olefin metathesis 40 antifungal agents, cationic complexes study 174 asymmetric ring closing metathesis antiselective substitution, mechanism 204 (ARCM) 40, 41, 335 antitumor reagents – using C1-symmetric NHCs 43 – copper complexes 195, 196 asymmetric ringopening cross-metathesis – metals 178–195 (AROCM) 40, 42, 335 –– auranofin/cisplatin, structure of 178 – E-selectivity in 44 –– gold–NHC systems 178 – E/Z selectivity 44 apoptotic pathway 181 – metathesis 44 Arrhenius law 130 Au–ADC catalysts 512 arylaldehydes 49 [Au(Br)(NHC)] 191 aryl alkyl ketones 54 [Au(Cl)(IMes)] 192 aryl/alky-substituted (NHC)Pt(dvtms) [Au(Cl)(IPr)] 188, 189 complexes 134 [Au(Cl)(NHC)] species 176 arylamine alkylation 353 AuI-bound binaphthyl isocyanides 515 arylation 357–359 Au(III) bis-NHC complexes 194 – C–H activation/deprotonation pathway 358 [Au(NHC)(PPh3)]PF6 complexes 192 – DFT calculations 357 [Au(OH)(IPr)], 188, 189 – of 2-phenylpyridine using 357 auranofin structure 178 arylboronic acids 49 azabicycles 48 aryl bromides 95, 96 aziridination 221 aryl chlorides 90 azolium salt 408 β-arylcycloalkanones 66 – deprotonation 408 aryl ether reduction 384 azomethine 247 3-aryl-3-fluoro-oxindole 60 aryl iodide, double carbonylation 214 b aryl magnesium bromides 68 Balz–Schiemann reactions 230 3-aryl-3-methyloxindole 59 Be–IPr complex 435 Aspergillus niger 151 bent allene resonance 519 asymmetric allylic substitution 219 benzimidazole-derived carbenes 94 asymmetric catalysis 97–100 benzimidazoles 273 – chiral bis-NHC ligand precursor and bis- benzimidazolin-2-ylidenes 94 NHC–Pd complex, synthesis 98 – ligands 94 – molecular design of iminoalkyl imidazolium benzimidazolium ligands 96 ligand 98 benzofurans 46, 349 asymmetric catalysis using NHC–Pd 63–65 benzophenone 345 – asymmetric allylic alkylation using benzothiazolium salts 346 NHC–Pd 65 benzothiophenes 47, 349 – asymmetric intermolecular α-arylation benzyl alcohol 353 –– using NHC as chiral modifiers of benzylamine 354 nanoparticles 63 N-benzylideneaniline 343 – asymmetric intramolecular oxidative N-benzylidenebenzylamine 354 amination 65 N-benzyl 2-phenylacetamide 354 Index 527 benzylpropargyl ether 140, 143 Buchwald–Hartwig aminations 88, 89, 509 beryllium–NHC complex 434 Burkholderia cepacia complex 154, 156 – ionic 434 bidentate (NHC)–Pd complexes 92, 94 c bidentate trans-chelating NHC-ligands 95 CAACs. See cyclic alkyl amino carbenes bifunctional catalysis 280 (CAACs) binaphthyl-2-2´-diamine (BINAM) 86 cancer cell lines 193 BIneoPent compound 119 – IC50, comparison of 185, 187, 190, 191, 196 BIN ligand 344 carbene 1,3-dimethyl-4,5-dimethylimidazol-2- bioxazoline-derived NHC complex 27 ylidene 398 bioxazolines 56 carbenes 1, 69 bis-amido NHC ligands 408 – abnormal 5, 6 bis(benzimidazolylidene) zirconium – derived from imidazolium salts 19 complex 408 – dihydrocarbene 5 bis(bis(trimethylsilyl)amino) magnesium(II) – electron distribution mapping 4 complex 437 – isodesmic calculations 5 bis-NHC CNC-type pincer ligands 410 – mesoionic 273 bis-NHC complexes, macrocyclic 166 – singlet 2, 7 bis-NHC–copper complexes 201, 214 – soft 282 bis(NHC)–lithium complex 432 – stable 1, 3, 5 bis(NHC)–Pd complexes 94 – triplet 1, 2 bis-phenoxide–NHC ligand 405 carbenoids 458 trans bis-silyl ethylene species 140 carboboration reactions 226 bis-silyl platinum carbene species 144 – mechanism for 227 – synthesis of 144 carbodicarbene 519 bis(trimethylsilyloxy)methylsilane 122, 125, carbon–nitrogen bond-forming reactions 382 144 carbon–sulfur bond-forming reactions 382, BMOL (bipotential murine oval liver) 181 383 [BnN(CH2CH2CH2RIm)2]PdCl2 96 carbonyl compounds, boration 223 N-Boc-7-azanorbornene 49 carbonyl functions, transformation of 226 bond dissociation energy 26 carbonyls, olefination “boomerang” effect 311 – [Cu(Cl)(NHC)], using 227 borocarboxylation carboxylation mechanism 214 – of alkyne 233, 234 caspase-3, 181 – proposed mechanism 234 catalyst activation 143, 144 boron 479–481 catalyst deactivation pathways 125–127 boronic acids 48–50 – (IPr)Pt(AE) by benzylpropargyl ether 144 boronium salt 480 catalyst screening 134–137 boron reagents catalysts derived from nickel(0) and nickel(II) – conjugated addition 210 sources 373 borrowing hydrogen 351–356 catalytic asymmetric allylic alkylation (AAA) – reaction with C-H activated complex 351 – with vinylaluminum reagents 219 boryl–copper complex [Cu(Bpin)(SIMes)] catalytic efficiency 31 234 cationic complexes studied borylene 480 – as antibacterial/antifungal agents 174 β-boryl ketones 71 cationic gold(I/III) complexes 177 B2pin2, allylic substitution 220 cationic NHC–copper complexes catalyzed breast cancer line MB157 cycloaddition reaction 216 – in vivo xenograft model 164 cationic transfer hydrogenation systems 344 N-(2-bromoaryl)-N-alkyl-2- chalcones 71 arylpropanamides 57 Chalk–Harrod mechanism 113, 123, 145 4-bromo-2,5-bis(hexyloxy)phenyl)magnesium Chalk mechanism 113, 123 chloride 105 charge distribution 4 528 Index Chauvin metallacyclobutane 307 copper–bifluoride complex 230 chelated bis(acyclic diaminocarbene) copper hydride species 200 complex 499 copper-mediated carboboration 226 chelated diallyl ether 144 copper–NHC complexes 211 chelates 93 – hydrothiolation, hydroalkoxylation and chiral acyclic carbene ligands 513 hydroamination catalyzed 211 chiral AuI–ADC complexes. Cr NHC complexes – enantioselective alkynylbenzaldehyde – in combination with MAO 414 cyclization/acetalization catalyzed by 515, – indenyl-functionalized NHC complexes 516 of 414 chiral bidentate NHC-bearing ruthenium – Schulz–Flory distribution 414 complexes 334 – supported by a chelating bis-(N-heterocyclic chiral bidentate phosphine–oxazoline carbene) ligand 414 ligands 39 cross-coupling reactions 85–93 chiral 6,6´-dimethoxybiphenyl-2,2´- – Buchwald–Hartwig aminations 88, 89 diamine 76 – Heck reaction 92, 93 chiral imidazolium tetrafluoroborates 57 – Hiyama coupling 89, 90 chiral NHC–CuCl catalyst 68 – Kumada coupling 90 chiral NHC–palladium complexes 91 – Negishi reactions 89 chiral NHC–Ru complex 40 – Sonogashira coupling 90–92 chiral palladium bis(ADC) catalysts – Suzuki–Miyaura Coupling 85–88 – enantioselective aza-Claisen rearrangement C-S/C-N bonds, formation 210 with 514 13C shielding tensor 4 chiral Ru complexes, bearing C-Si bonds formation, from addition of – binaphtholate and biphenolate substituted halosilane to Sc–NHC complexes 399 NHCs 335 Cu-catalyzed allylic alkylation – 4,5-di-tert-butyl-substituted unsymmetrical – using in situ generated ADC ligand 509 NHCs 333 [Cu(Cl)(IMes)], imidazole derivatives 220 – monosubstituted backbone bearing [Cu(Cl)(IPr)] 200 NHCs 334 [Cu(Cl)(NHC)] chiral Ru metathesis catalysts 332 – NHC-copper systems of 223 chiral ruthenium
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  • I. Total Synthesis of (+)-Spongiolactone and Derivatives

    I. Total Synthesis of (+)-Spongiolactone and Derivatives

    I. TOTAL SYNTHESIS OF (+)-SPONGIOLACTONE AND DERIVATIVES ENABLING INITIAL STRUCTURE-ACTIVITY RELATIONSHIP STUDIES: DISCOVERY OF A MORE POTENT DERIVATIVE II. STUDIES TOWARD RECYCLABLE ISOTHIOUREA CATALYSTS A Dissertation by NATALIE LAURA HARVEY Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Chair of Committee, Daniel Romo Committee Members, Daniel Singleton David Bergbreiter Thomas McKnight Head of Department, Francois Gabbai December 2015 Major Subject: Chemistry Copyright 2015 Natalie Laura Harvey ABSTRACT β-lactone containing natural products are attractive targets for total synthesis and subsequent biological studies. Given the remarkable ability of this moiety to covalently inhibit specific proteins, we were drawn to spongiolactone as a synthetic target. Through our studies, the first total synthesis of this compound was achieved along with the synthesis of several derivatives. This synthesis enabled cytotoxicity studies to be carried out against a variety of cancer cell lines, with good activity observed in the human chronic myelogenous leukemia (K562) cell line. Particularly intriguing was the discovery of a more potent derivative than the natural product itself which was then modified and taken on to activity based protein profiling (ABPP) studies. The first magnetite-supported benzotetramisole (BTM) catalyst was prepared and utilized in the kinetic resolution of secondary alcohols. Overall, the selectivity factor was lower than the parent (+)-BTM (s = 48 versus s = 148, respectively), however the resulting ester was achieved in excellent enantiomeric excess, albeit with low reaction conversion. Further studies suggest an unfavorable inactivation of the catalyst taking place in the presence of uncapped magnetite.