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Advances in Heterocylic Chemestry. Vol 10 - Boulton A.J.

Boulton A.J. Advances in Heterocylic Chemestry. Vol 10 - Academic Press, 1969. - 347 p.
Download (direct link): advensisheroklinik1969.pdf
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309 G. I. Zhungietu and E. M. Perepelitsa, Zh. Obshch. Khim. 36, 1858 (1966).
310 K. Hafner, Org. Synth. 44, 96 (1964).
311 W. Schneider and H. Keller, Ber. Deut. Chem. Ges. 74, 729 (1941).
312 C. Harries, Ber. Deut. Chem. Ges. 32, 1326 (1899); Ann. Chem. 330, 185 (1904).
313 H. Hibbert, J. Am. Chem. Soc. 37, 1748 (1915).
314 J. Doeuvre, Bull. Soc. Chim,. France Ser. 4 39, 1594 (1926).
315 H. C. Volger and W. Brockman, Bee. Trav. Chim. 84, 1017 (1965).
316 G. Hesse, R. Hatz, and U. Dutt, Chem. Ber. 100, 923 (1967).
317 G. Dupont and L. Menut, Bull. Soc. Chim. France Ser. 5 6, 1215 (1939).
318 J. Kenyon and D. P. Young, J. Chem. Soc. p. 1547 (1940).
319 √. H. Stross, J. M. Monger, and H. de V. Finch, J. Am. Chem. Soc. 69, 1627 (1947).
32į jj p Gray, R. S. Rasmussen, and D. D. Tunnicliff, J. Am. Chem. Soc. 69, 1630 (1947).
321 J. Wiemann and L. Martineau, Compt. Bend. 246, 131 (1958).
oxide, the equilibrium concentration is ca. 9%.815,316 The isomers can be separated319 by careful fractionations avoiding acidic or alkaline catalysts which immediately restore the equilibrium. Praill and Whitear322 showed that by acetylating (Ac20 + HC104) 4-methyI-4-penten-2-one (isomesityl oxide) (80) instead of mesityl oxide (78), the yield of trimethylpyrylium perchlorate was raised from ca. 40 to 87%, which strongly suggests that 80 is the active form (the C=CH2 group, not being conjugated with the carbonyl group, behaves normally). A case in which a /?,y-unsaturated isomer prevails owing to conformational reasons is that of cyclohexenylacetone (81, R=-Me) or cyclohexenylacet6phenone (81, R = Ph) which lead to Bz-tetrahydroisochromylium salts (82) in 50-90% yields, as shown by Dorofeenko and co-workers.823-327 By the irreversible formation of the resonance-stabilized pyrylium cation, the equilibrium (78 ^ 80) is shifted to the right. This method allowed the prepration of 5,6,7,8-tetrahydroisobenzopyrylium salts (82) with p-anisyl substituents328; by starting from 5- or 7-membered cycloalkanones, pyrylium salts with fused saturated rings were prepared.S29> 330 Pulegone also
322 p p Q. Praill and A. L. Whitear, J. Chem. Soc. p. 3573 (1961).
323 G. N. Dorofeenko and ”. I. Dulenko, Zh. Obshch. Khim. 32, 3445 (1962).
324 L. V. Dulenko, V. I. Dulenko, and G. N. Dorofeenko, Zh. Obshch. Khim. 34, 3588 (1964).
325 G. N. Dorofeenko, ”. I. Dulenko, and L. V. Dulenko, Zh. Obshch. Khim. 34, 3116 (1964).
326 G. N. Dorofeenko and V. I. Dulenko, Dokl.Akad. NaukSSSB 157,361 (1964).
327 G. N. Dorofeenko, G. P. Safaryan, and V. I. Dulenko, Zh. Obshch. Khim. 36, 811 (1966).
328 G. N. Dorofeenko, Habilitation Thesis, Rostov/Don, 1965; S. V. Krivun, Ph.D. Thesis, Rostov/Don, 1965; V. I. Dulenko, Ph.D. Thesis, Rostov/Don, 1965.
329 G. N. Dorofeenko, Y. A. Zhdanov, V. I. Dulenko, V. A. Palchkov, and N. V. Kovalenko, Khim. Ceterotsikl. Soedin. Akad. Nauk Latv. SSB p. 172
(1966).
330 Y. A. Zhdanov, G. N. Dorofeenko, and V. A. Palchkov, Khim. Geterosikl. Soedin. Akad. Nauk Latv. SSB p. 812 (1965).
affords on acetylation a pyrylium salt.331 ň„-A Iky 1 - i ruloly I - acetones and similar glycosidic derivatives are acylated to indole[2,3-c]-pyrylium salts.831ŗ,ķ
Acylation of indenylindenones leads to indenopyrylium salts.332 A related reaction is the acylation of 3,4-disubstituted benzyl ketones to isobenzopyrylium salts833-337 ; the unsubstituted compounds yield
4-pyrones as shown in Section II,D,3,a. Another related acylation converts unsaturated esters into 2-pyrones, e.g., ethyl /3,/3-dimethyl-acrylate into 4,6-dimethyl-2-pyrone.109
The anhydride or acyl chloride and the catalyst (proton acid or Lewis acid) interact leading to the acylating agent [formulated here for brevity as an acyl cation (83)].13,14,282,338,389
(RóC0)20 + HX -----------RóCO+X- + RCOOH
(RóC0)20 + MHalĄ --------Ľ¶ RóC0++ RCOOMHaln-
RóCOHal + MHaln ---------> RóCO+ + MHalJ+i
RóCOOH + 2HX ------------> RóCO+X- + HaO+X-
(83)
b. From Unsaturated Ketones and Aldehydes, with Dehydrogenation. This reaction leads to 2,4-pentadien-l-ones (type in Section II,B,2,e)
331 G. N. Dorofeenko and G. I. Zhungietu, Zh. Obshch. Khim. 35, 963 (1965). 331ď G. N. Dorofeenko and V. I. Dulenko, USSR Patent No. 194,093 (1967).
331b Yu. A. Zhdanov, V. T. Kornilov, a,nd G. N. Dorofeenko, Dokl. Akad. Nauk
SSSR 178, 849 (1968); G. N. Dorofeenko and Y. G. Korobkova, Chem. Ind.
(London) p. 1848 (1968).
332 Y. A. Zhdanov, G. N. Dorofeenko, and ”. A. Palchkov, Zh. Obshch. Khim,
35, 827 (1965).
333 G. N. Dorofeenko, S. Y Krivun, and V. I. Dulenko, USSR Patent No. 176,592 (1965).
334 G. N. Dorofeenko, L. V. Dulenko, Y. I. Dulenko, and S. V. Krivun, Zh. Organ. Khim. 1, 1171 (1965).
335 G. N. Dorofeenko, A. D. Semenov, V. I. Dulenko, and S. V. Krivun, Zh. Organ. Khim. 2, 1492 (1966).
336 G. N. Dorofeenko, E. V. Kuznetsov, and S. V. Krivun, Zh. Organ. Khim.
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