作者:William R. Dolbier、Suk Kyu Lee、Otto Phanstiel
DOI:10.1016/s0040-4020(01)96116-2
日期:——
nmr indicated the presence of acyl ammonium salts and enolates, potential precursors of the ketenes, but no actual ketene species could unambiguously be detected. The stereochemical results were consistent with the currently accepted steric-based mechanistic rationale for stereochemical determination in ketene cycloadditions.
经由各自的酰氯的脱卤化氢,分别原位产生氟代烯,二氟代烯,甲基氟代烯,三氟甲基氟代烯和苯基氟代烯。在存在环戊二烯的情况下,除了二氟乙烯烯外,均获得了[2 + 2]加合物。在不存在环戊二烯的情况下,低温19 F nmr指示存在烯酮的潜在前体酰基铵盐和烯醇化物,但无法明确检测到实际的烯酮物种。立体化学结果与目前公认的基于乙烯的环烯加成中立体化学测定的基于机理的机理基本一致。