Intramolecular Copper- and Rhodium-Mediated Carbenoid Reactions of α-(Propargyloxy)silyl-α-diazoacetates
作者:Volker Gettwert、Fred Krebs、Gerhard Maas
DOI:10.1002/(sici)1099-0690(199905)1999:5<1213::aid-ejoc1213>3.0.co;2-u
日期:1999.5
Copper(I) triflate catalyzes the transformation of α-[(2-alkynyl)oxy]silyl-α-diazoacetates 1a–g into 1,2-bis(2,5-dihydro-1,2-oxasilol-4-yl)ethenes 2 and/or 2H-1,2-oxasilines 3. With rhodium(II) perfluorobutyrate as catalyst, 1a–e furnish only 3 but no 2. Bicyclic 2-methoxyfurans 6 are formed when 1a,c,e (containing terminal alkyne functions) are treated with catalytic amounts of copper(I) chloride
三氟甲磺酸铜(I)催化α-[(2-炔基)氧基]甲硅烷基-α-重氮乙酸酯1a-g转化为1,2-双(2,5-二氢-1,2-oxasilol-4-yl)乙烯 2 和/或 2H-1,2-oxasilines 3. 用全氟丁酸铑 (II) 作为催化剂,1a-e 只提供 3 而没有 2。当 1a,c,e(包含末端炔烃)时形成双环 2-甲氧基呋喃 6功能)用催化量的氯化铜(I)处理。实验观察结果通过金属介导的分子内环丙烯化和随后的金属辅助开环的张力双环环丙烯开环来解释,导致乙烯基卡宾 - 金属配合物。还描述了 2H-1,2-oxasilines 3a,c,e 的异常自动氧化。