Synthesis of 6-formylsalicylates based on regioselective [3+3] cyclocondensations of 1,3-bis(silyloxy)-1,3-butadienes with 1,1-dichloro-4-ethoxy-3-buten-2-ones
摘要:
6-Formylsalicylates are prepared by regioselective [3+3] cyclocondensations of L3-bis(silyloxy)-1,3-butadienes with 1,1-dichloro-4-ethoxy-3-buten-2-ones and subsequent transformation of the dichloromethyl into a formyl group. (C) 2009 Elsevier Ltd. All rights reserved.
First synthesis of functionalized 5-aryl-3-(trifluoromethyl)phenols by regioselective [3+3] cyclocondensations of 1,3-bis(silyloxy)-1,3-butadienes with 3-aryl-3-silyloxy-1-trifluoromethyl-2-en-1-ones
A variety of functionalized 5-aryl-3-(trifluoromethyl)phenols were prepared by the first TiCl4-mediated [3+3] cyclocondensation of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-aryl-3-trimethylsilyloxy-1-trifluoromethyl-2-en-1-ones.
Synthesis of Functionalized Biaryls Based on a Heck Cross-Coupling-[3+3] Cyclization Strategy
作者:Peter Langer、Gerson Mroß、Helmut Reinke
DOI:10.1055/s-2008-1072654
日期:——
6-Arylsalicylates were regioselectively prepared by formal [3+3] cyclization of 1,3-bis(silyloxy)-1,3-butadienes with 1-aryl-3-ethoxyprop-2-en-1-ones which are available by Heck reaction of benzoyl chlorides with ethylvinyl ether. In this context, the first [3+3] cyclizations of brominated substrates are reported.
The formal [3+3] cyclization of 1,3-bis(silyloxy)buta-1,3-dienes with 1-aryl-3-ethoxyprop-2-en-1-ones, available by Heck reaction of benzoyl chlorides with ethyl vinyl ether, afforded a variety of 6-arylsalicylates. The reaction of the products with concentrated sulfuric acid resulted in the formation of fluorenones. 6-Alkylsalicylates were prepared by cyclization of 1,3-bis(silyloxy)buta-1,3-dienes
Regioselective synthesis of 4-acyl-1-hydroxy-2,3-benzodioates by chelation-controlled [3+3] annulation of 3-acyl-4-ethoxy-2-oxo-3-enoates with 1,3-bis(trimethylsilyloxy)-1,3-butadienes
作者:Abdolmajid Riahi、Mohanad Shkoor、Olumide Fatunsin、Rasheed Ahmad Khera、Christine Fischer、Peter Langer
DOI:10.1039/b905556h
日期:——
4-Acyl-1-hydroxy-2,3-benzodioates were regioselectively prepared by chelation-controlled [3+3] cyclization of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-acyl-4-ethoxy-2-oxo-3-enoates.
Regioselective [3+3] Cyclization of 1,3-Bis(silyloxy)buta-1,3-dienes with 1,1,1-Trifluoro-4-(silyloxy)alk-3-en-2-ones: New and Convenient Synthesis of Functionalized 5-Alkyl-3-(trifluoromethyl)phenols
作者:Stefan Büttner、Alina Bunescu、Sebastian Reimann、T. H. Tam Dang、Thomas Pundt、Renske Klassen、Andreas Schmidt、Nazken K. Kelzhanova、Zharylkasyn A. Abilov、Tariel V. Ghochikyan、Ashot S. Saghiyan、Alexander Villinger、Helmut Reinke、Anke Spannenberg、Peter Langer
DOI:10.1002/hlca.201200056
日期:2013.1
Functionalized 5‐alkyl‐3‐(trifluoromethyl)phenols were prepared by formal [3+3] cyclization of 1,3‐bis(silyloxy)buta‐1,3‐dienes with 1,1,1‐trifluoro‐4‐(silyloxy)alk‐3‐en‐2‐ones derived from 1,1,1‐trifluoroalkane‐2,4‐diones. The latter were prepared by condensation of the dianion of 1,1,1‐trifluoropentane‐2,4‐dione with alkyl halides.