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Organic Seminar Abstracts L I B RA R.Y OF THE UN IVE.R.SITY Of ILLI NOIS 547 l£6s \ 954/55 PV Return this book on or before the Latest Date stamped below. University of Illinois Library Llf.1—H41 Digitized by the Internet Archive in 2012 with funding from University of Illinois Urbana-Champaign http://archive.org/details/organicsemi195455univ \7^ — SEMINAR TOPICS CHEMISTRY 435 I Semester 1954-55 The Quinolizinium Ion and Some of its Derivatives Harvey M. Loux, September 24 1 The Stereochemistry of Atropine and Cocaine Ho E . Knipmeyer, September 24 4 Recent Developments in the Chemistry of Cinnoline Derivatives Roger H. Kottke , October 1 8 Interpretation of Electrophiiic Aromatic Substitution and Solvolysis of Allylic and Benzhydryl Chlorides in Terms of Hyperconjugation Robert D. Stolow, October 1 11 The Decahydronaphtholic Acids and Their Relationship to the Decalols and the Decalylamines Robert J. Harder, October 8 14 Bis-Cyclopentadienyl Metal Compounds Edwin L. DeYoung, October 8 17 Ion-Pairs as Intermediates in Solvolysis Reactions Arthur H. Goldkamp, October 15 21 Synthesis of Morphine Mohan D. Nair, October 15 24 Structural and Geometrical Isomerism in the Oxidation of Azo Compounds D. F. Morrow, October 22 27 Stereochemical Aspects of Thermochromism John W. Johnson, Jr., October 22 30 A New Method for the Preparation of Olefins --The Pyrolysis of Sulfites F. M. Scheidt, October 29 33 Recent Studies of Macrocyclic Ring Systems: Cyclophanes Fred P. Hauck, Jr., October 29 36 Mechanism of the Para-Claisen Rearrangement Hugh H . Gibbs , November 5 40 A Proposed Mechanism for Basic c is -Dehydrohalogenat ion Robert M. Nowak, November 5 43 The Synthesis of Symmetrical Bibenzyl and Stilbene Compounds From Nitrotoluenes F. W. Wassmundt, November 12 45 1,2-Benzisothiazolones Frederick H. Owens, November 12 48 -2- The Synthesis of Oxytocin Wendell W. Moyer, Jr., November 19 51 Synthesis and Properties of Dithiadiene and Some Related Compounds Ralph Farrar, November 19 5^ Carbonium Ion Rearrangements in Three and Four Membered Rings J . W . Crump , December 3 57 The Mannich Reaction with Nitroparaff ins Bernard Freedman, December 3 6l Diels-Alder Reactions of Azodicarboxylic Ester R. L. Pedrotti, December 10 64 The Stereochemical Interrelation of Terpenes and Sugars Ronald R. Sauers, December 10 67 Chemical Structure and Carcinogenic Activity Paul Tomboulian, December 17 70 Sulfenic Acids and Their Derivatives Charles A. Plantz, December 17 73 Poison Ivy "Urushiol" William G. DePierri, Jr., January 7 75 The Oxidation of Primary Aromatic Amine by Phenyl Iodosoacetate Eiichi Tanda, January 7 77 Mechanisms of the Dehydroge nation of Dihydroaromatic Compounds by Quinones Richard C . Thamm, January Ik 80 : . THE QUINOLIZINIUM ION AND SOME OF ITS DERIVATIVES Reported by Harvey M. Loux September 24, 1954 The quinolizinium ion was first proposed and proved con- 1 ' 2 clusively ""in 1949 by Woodward and coworkers to be a constituent of the alkaloid sempervirine Several investigators 2 ' 3 ' 4 have synthesized quinolizinium salts substituted in positions 2 and 3 (I) by the following procedure CH2 Li '/ 0=C-R 8 Mo + > il I N HC=C-R' 7 i V ' OR' 6 © 4 This method gives very poor yields for the unsubstituted 5 salts. Boekelheide and Gall , however, have recently developed a good synthetic procedure by which quinolizinium iodide may be obtained in fair yields. CH CH L1 2 </ 2 0=CH CH-OH + -> 1. HI ! i N CH2 -CH2 N ,CH2 2. K2 C0 3 ch/ V I OEt I OEt II \J/ OH '/ x Pd(C) '/y^ Ac 2 o V' <? ^ N H2 S04 V©vN G> e I V TV III The quinolizinium iodide is quite soluble in water and is readily transformed into perchlorate and picrate salts. It absorbs five moles of hydrogen catalytically to form quinolizidine . The structure of the carbinol (III) was established by reduction to 2-hydroxyquinolizidine followed by oxidation to 2-quinolizidone . This was identified as the picrate, previously described. Quite recently Brad she r and Beavers 6 have reported the synthesis of benzoquinolizinium salts by methods of aromatic cyclodehydration. These methods eliminate the necessity for dehydrogenation and are well suited for the synthesis of com- pounds which are sensitive to high temperatures. By treating a-phenylpyridine with a-iodcacetone they obtained N-acetonyl-a- phenylpyridinium iodide (VI). Keating under reflux with 48$ -2- hydrobromic acid for fifty-one hours brought about ring closure to 7-methylbenzo[a]quinolizinium bromide (VII) in 75$ yield. HEr -> ^> VI VII Oxidation of VII with permanganate to give phthalic acid together with ultraviolet absorption studies provided evidence supporting the structure suggested. By using phenacyl bromide in place of a-iodoacetone, the phenyl -substituted benzo- quinolizinium salt was obtained in 42$ yield. Since the phenacyl 7 salt has a lower cyciization rate than the acetonyl salt this reaction required fourteen days for completion. The protoberberine alkaloids contain the dibenzodihydro- quinolizinium skeleton (VIII ) with methoxy, methylenedioxy, and hydroxy substituents on positions 2, 3 » 9* and 10. Included among the more common of these alkaloids are berberine 8 (IX), 8 ' 9 8,1 8 * 11 columbamine , coptisine °, and palmatine . Nt® v O W% X O 0CH< OCHr VIII IX . The alkaloid sempervirine was assigned structure X by Prelog 12 in 1948 on the basis of degradative studies. In 1949 Woodward and Witkop 1 suggested structure XII as being in better agreement with the color and with the fact that the infrared absorption spectrum of sempervirine contains no N-H band, whereas all N-unsubstituted indoles have a sharp peak at 2.9 m^y . The ionic structure (XIII ) containing the quinolizinium ion would contribute an important part to the actual configuration of sempervirine. This fact makes understandable the formation of metho-salts of structure XI as well as the color and high basicity of the alkaloid. -3- y\ ^/ ^ —/^ J\ A <r ^ *i N © N V vwx VVVe XII XIII At about the same time Woodward and McLamore 2 carried out a synthesis of sempervirine methochloride which confirmed their proposed structure. The reaction was a condensation of N -methyl- harman (from N -methyl tryptophane ) with isopropoxymethylenecyclo- hexanone in a manner similar to that given for the preparation of I. Schwyzer 13 has reported a method for transforming an alkaloid of the yohimbine type into one of the sempervirine type Bibliography 1. R. B. Woodward and B. Witkop, J. Am. Chem. Soc . 71, 379 (1949). 2 R. B. Woodward and W. M. McLamore, ibid . , 71, 379 (1949). 3 A. G. Beaman, Ph.D. Thesis, Harvard University, 1951- 4 A. Richards and T. S. Stevens, Chemistry and Industry 1954 , 905- 5 V. Boekelheide and W. G. Gall, J. Am. Chem. Soc. 76, 1832 ( 195*0 6 C. K. Bradsher and L. E. Beavers, Abstracts of Papers Presented at New York A. C .S. -Meeting, Sept., 195*1- 7 C. K. Bradsher and F. A. Vingiello, J. Am. Chem. Soc. 71, 1434 (1949). 8 R. H. F. Manske and H. L. Holmes, "The Alkaloids," Vol. 4, Academic Press, Inc., New York, 1954, pp. 77-118. 9. E. Sp'ath and E. Masettig, Ber. 60, 383 (1927). 10, E. Sp'ath and R. Posega, ibid., Eg, 1029^(1929). 11, R. D. Haworth, et . al . , J." Chem. Soc. 1927, 548. 12, V. Pralog, Helv. Chim. Acta 31, 588 (194~&7. 13. R. Schwyzer, ibid . , 35 , 867 (1952). -4- THE STEREOCHEMISTRY OF ATROPINE AND COCAINE Reported by H. E. Knipmeyer September 24, 1954 Atropine CH2 OH CH2 - CH - CH2 la: R = -C-CH-C 6 H 5 I I M-CK3 CK - OR lb: R = -H • l i CH2 - CH - CH2 Atropine (la) has been shown to be an ester of tropic acid and the amino alcohol tropine (lb). 1 Two geometrical isomers of tropine should be capable of existence. Their three-dimensional formulae are shown in structures II and III. .N-CH3 N-CHa NrCH 3 The isomer of tropine, pseudotropine, was prepared by Willstasttor2 by the reduction of tropinone (Jv) under basic condi- tions. Tropine may be epimerized to pseudotropine in the presence of base, but the reverse is possible only by oxidation to the ketone followed by reduction with zinc dust and hydriodic 2 ' 3 acid. Tropinone may also be selectively reduced by LiAlK4 to pseudotropine 4 The acid-catalyzed stereospecific migration of acyl groups 5 from nitrogen to oxygen and the reverse migration under the influence of dilute alkali has ^oeen applied by Fodor to elucidate the configuration of the hydroxy1 group relative to that of the nitrogen bridge. Fodor and Nador, 6 whose work has been confirmed by Fieser, 7 found that N-benzoylnorpseudotropine was transformed into O-benzoyinorpseudotropine by acid and that the reverse re- action took place when the O-benzoyl compound was treated with alkali. In contrast to this the epimeric nortropine analogs gave no reaction under identical conditions. From this work it is evident that norpseudotropine (and analogously the N-methyl compounds) must have the nitrogen atom and the hydroxy 1 group in an a - or els - relationship to one another in order to permit the existence of the cyclic inter- mediate involved in the rearrangement. Thus, structure II may be assigned to tropine and structure III to the epjmeric pseudotropine An additional problem is whether the piperidine _ .— ring exists in the boat (V) or chair (III) form. It • is difficult to predict which form of the piperidine - ring is better in the bicyclic system under dis- cussion for a chair conformation of the piperidine ring would necessitate a boat form for the cycloheptane ring. However the evidence seems to favor the chair conformation. J .1 Sparke 8 has interpreted the base -catalyzed eplmerizaticn of tropine to pseudotropine and the s elective reduction of tropinone to the pseudo isomer in terms of t he concept of axial and equatorial bonds 9 and has conclude d that pseudotropine should have an equatorial hydroxy1 group as this configuration is known to be the more stable one.
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