Regioselective Synthesis of 6-[Chloro(difluoro)methyl]salicylates by [3+3] Cyclocondensations of 1,3-Bis(trimethylsilyloxy)buta-1,3-dienes with 1-Chloro-1,1-difluoro-4-(trimethylsilyloxy)pent-3-en-2-one
作者:Silke Erfle、Sebastian Reimann、Alina Bunescu、Zharylkasyn A. Abilov、Anke Spannenberg、Peter Langer
DOI:10.1002/hlca.201100494
日期:2012.6
cyclocondensation of various 1,3‐bis(trimethylsilyloxy)buta‐1,3‐dienes with 1‐chloro‐1,1‐difluoro‐4‐(trimethylsilyloxy)pent‐3‐en‐2‐one provides a regioselective access to novel 6‐(chlorodifluoromethyl)salicylates (=6‐(chlorodifluoromethyl)‐2‐hydroxybenzoates) with very good regioselectivity. For selected products, it was demonstrated that the CF2Cl group can be transformed to CF2H and CF2(Allyl) by free‐radical
Regioselective Synthesis of Highly Functionalized Arylphosphonates by Cyclocondensation of 1,3-Bis(trimethylsilyloxy)buta-1,3-dienes with 3-Ethoxy-2-phosphonylalk-2-en-1-ones
Highly functionalized arylphosphonates were prepared by TiCl 4 -mediated cyclocondensation of 3-ethoxy-2-phosphonylalk-2-en-1-ones with 1,3-bis(trimethylsilyloxy)buta-1,3-dienes.
Synthesis of trifluoromethyl-substituted salicylates by cyclocondensation of 1,3-bis(silyloxy)-1,3-butadienes with 4,4-dimethylthio-1,1,1-trifluorobut-3-en-2-one
作者:Viktor O. Iaroshenko、Alina Bunescu、Lutz Domke、Anke Spannenberg、Dmitri V. Sevenard、Alexander Villinger、Vyacheslav Ya. Sosnovskikh、Peter Langer
DOI:10.1016/j.jfluchem.2011.04.011
日期:2011.7
A formal [3+3] cyclocondensation of 1,3-bis(silyl enol ethers) with the little-known 4,4-dimethylthio-1,1,1-trifluorobut-3-en-2-one was studied. In contrast to 4,4-dimethoxy-1,1,1-trifluorobut-3-en-2-one, this alpha-oxoketene dithioacetal reacts with 1,3-bis(trimethylsilyloxy)-1,3-butadienes in the presence of TiCl4 to give mainly 6-methylthio-4-(trifluoromethyl)salicylates via 1,2-addition. The scope and limitations of the reaction are discussed. (C) 2011 Elsevier B.V. All rights reserved.