On the methylation of 3-cyano-6-hydroxypyridine-2(1H)-ones
作者:Yves Louis Janin、Jaouad Chiki、Michel Legraverend、Christiane Huel、Emile Bisagni
DOI:10.1016/s0040-4020(99)00755-3
日期:1999.10
In order to prepare new heterocyclic derivatives as building block for compounds with potential biological activities, we were led to study the O-methylation of 3-cyano-6-hydroxypyridine-2(1H)-ones such as 1. This enabled us to develop a new two steps method to prepare the corresponding 2,6-dimethoxy derivative 5 in 80 % yield. It consisted first in heating 1 in trimethylorthoformate, with or without an acidic catalyst, which gave a mixture of the two mono-methoxy isomers, then a classical methylation of the second hydroxy moiety led almost exclusively to 5. In this paper we present this "methylation" method and various unexpected results recorded when we attempted to extend it to related derivatives or to other heterocycle containing lactim-lactam functions. An intramolecular transetherification mechanism requiring the simultaneous transfer of a hydrogen and a methyl is suggested. (C) 1999 Elsevier Science Ltd. All rights reserved.
Derivatives of azaindoles. 65. Synthesis of 1-benzyl-4-methyl-5-cyano-6-hydroxy-7-azaindoline
作者:T. V. Sycheva、E. F. Kuleshova、L. N. Yakhontov
DOI:10.1007/bf00513579
日期:1984.8
Ritchie, Australian Journal of Chemistry, 1956, vol. 9, p. 244,249
作者:Ritchie
DOI:——
日期:——
SYCHEVA, T. V.;KULESHOVA, E. F.;YAXONTOV, L. N., XIMIYA GETEROTSIKL. SOEDIN., 1984, N 8, 1105-1109
作者:SYCHEVA, T. V.、KULESHOVA, E. F.、YAXONTOV, L. N.
DOI:——
日期:——
3,4-Substituted Pyridines. I. Synthesis of 3-Vinyl-4-methylpyridine
作者:Joseph R. Stevens、Ralph H. Beutel、Earl Chamberlin