Synthesis of some cyclic and acyclic nucleoside analogues derived from 4-(trifluoromethyl)pyrimidines
摘要:
Cyclic nucleoside analogues 10, 11, 13b-d and 17 and acyclic derivatives 19 and 20b-d were prepared from 4-trifluoromethyl-pyrimidones 4a and 5b-d. (C) 2001 Elsevier Science Ltd. All rights reserved.
Reactions of Conjugate Phosphinyl- and Phosphonyl-Nitroso Alkenes with Enamines. Preparation of <i>N</i>-Hydroxypyrrole Derivatives
作者:Jesús M. de los Santos、Roberto Ignacio、Domitila Aparicio、Francisco Palacios、José M. Ezpeleta
DOI:10.1021/jo900489j
日期:2009.5.1
The synthesis of highly functionalized N-hydroxypyrrole derivatives by the formal [3+2] cycloadditionreaction of enamines and nitroso alkenes derived from phosphine oxides and phosphonates is reported. Intermediate phosphorylated nitrones, whose formation can be explained by a conjugate addition of enamines to phosphorylated nitroso alkenes and formation of the five-membered heterocycles, are isolated
Igarashi, Mamoru; Tada, Masaru, Journal of Heterocyclic Chemistry, 1995, vol. 32, # 3, p. 807 - 810
作者:Igarashi, Mamoru、Tada, Masaru
DOI:——
日期:——
A Facile New Synthesis of Aldehyde Enamines in High Yield and High Purity
作者:Gary B. Fisher、Lawrence Lee、Frederick W. Klettke
DOI:10.1080/00397919408010154
日期:1994.6
Aldehyde enamines were synthesized in excellent yield and purity by reacting an aldehyde with 2 equivalents of a secondary amine in cyclohexane in the presence of 1.5 equivalents of CaH2. Distilled yields ranged from 65%-92%.
Boranes in Synthesis. 5. The Hydroboration of Enamines with Mono- and Dialkylboranes. Asymmetric Synthesis of .beta.-Amino Alcohols of Moderate Enantiomeric Purity from Aldehyde Enamines
作者:Gary B. Fisher、Christian T. Goralski、Lawrence W. Nicholson、Dennis L. Hasha、Donald Zakett、Bakthan Singaram
DOI:10.1021/jo00112a026
日期:1995.4
The hydroboration of both acyclic and cyclic aldehyde and ketone enamines with such representative mono- and dialkylboranes as thexylborane and dicyclohexylborane, followed by an oxidative workup, yields the corresponding beta-amino alcohols in good to excellent isolated yields. The hydroboration of ketone and aldehyde enamines with the asymmetric hydroboration reagents monoisopinocampheylborane ((d)IpcBH(2)) and diisopinocampheylborane ((d)Ipc(2)BH) was also investigated, (d)Ipc(2)BH is highly effective for the asymmetric hydroboration of acyclic aldehyde enamines, such as 1-(4-morpholino)-3-phenyl-1-propene and 1-(1-pyrrolidino)-1-octene. Oxidation of the intermediate trialkylborane furnishes the corresponding beta-amino alcohols in 50-86% ee. The stereogenic center of the carbinol carbon is consistently enriched in the R-enantiomer when (d)Ipc(2)BH prepared from (+)-alpha-pinene is used as the hydroboration reagent. The enantiomeric excesses of the beta-amino alcohols synthesized in this study were determined by HPLC using a chiral stationary phase. The absolute configurations of some of the beta-amino alcohols synthesized in this study were determined by chiral HPLC comparison with authentic beta-amino alcohols prepared from chiral epoxides of known absolute configuration.
OHTA, KAZUKO;SHIMIZU, HIROKO;NOMURA, YUJIRO, NIPPON KAGAKU KAJSI,(1989) N, S. 846-854