Regioselective Synthesis of 5-(2-Methoxyethyl)biphenyls by Formal [3+3] Cyclocondensations of 1,3-Bis(trimethylsilyloxy)-1,3-butadienes
作者:Franziska Bendrath、Verena Specowius、Zharylkasyn A. Abilov、Ashot. S. Saghyan、Christine Fischer、Peter Langer
DOI:10.5560/znb.2013-2298
日期:2013.4.1
5-(2-Methoxyethyl)biphenyls have been prepared by regioselective formal [3+3] cyclocondensations of 1,3-bis(trimethylsilyloxy)-1,3-butadienes. Graphical Abstract Regioselective Synthesis of 5-(2-Methoxyethyl)biphenyls by Formal [3+3] Cyclocondensations of 1,3-Bis(trimethylsilyloxy)-1,3-butadienes
Synthesis of 2-Alkylidenepyrrolidines, Pyrroles, and Indoles by Condensation of Silyl Enol Ethers and 1,3-Bis-Silyl Enol Ethers with 1-Azido-2,2-dimethoxyethane and Subsequent Reductive Cyclization
作者:Esen Bellur、Helmar Görls、Peter Langer
DOI:10.1021/jo047856x
日期:2005.6.1
The condensation of 1,3-bis-silylenolethers with 1-azido-2,2-dimethoxyethane and subsequent reductive cyclization allowed an efficient regio- and diastereoselective synthesis of a variety of 2-alkylidene-4-methoxypyrrolidines. The thermal elimination of methanol resulted in the formation of functionalized pyrroles. Similarly, 2,3,3a,4,5,6-hexahydro-2,3-benzopyrroles were prepared and transformed
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.
Domino Michael/Retro-Michael/Mukaiyama-Aldol Reactions of 1,3-Bis-Silyl Enol Ethers with 3-Acyl- and 3-Formylbenzopyrylium Triflates – Synthesis of Functionalised 2,4′-Dihydroxybenzophenones
3-bis-silyl enol ethers with 3-acyl- and 3-formylbenzopyrylium triflates, which can be generated in situ from 3-acyl- and 3-formylchromones, affords a great variety of functionalised 2,4′-dihydroxybenzophenones and 4-(2-hydroxybenzoyl)salicylates. These products are formed by a domino Michael/retro-Michael/Mukaiyama-aldol reaction. This methodology is successfully applied to the synthesis of novel UV-A/B and