Hydro-De-Phosphoniation of 4-Substituted-4-Triphenylphosphonio-5(4<i>H</i>)-Oxazolones With Alcohols
作者:Roman Mazurkiewicz、Anna W Pierwocha、Anna Brachaczek、Iwona Mitrus
DOI:10.1080/10426500008076324
日期:2000.2
Abstract 4-Substituted-4-triphenylphosphonro-5(4H)-oxazolones with a bulky alkyl substituent at the position 4 treated with MeOH in the presence of DBU (1.8-diazobicyclo[5.4.0]undec-7-ene) at room temperature give corresponding N-acyl-α-amino acid esters. In the case of a smaller substituent at the position 4 (Me, MeOCH2), the triphenylphosphonium group was competitively displaced by the methoxy group
摘要 4-取代的-4-三苯基膦酰基-5(4H)-恶唑酮在室温下在 DBU(1.8-重氮双环[5.4.0]十一碳-7-烯)存在下用 MeOH 处理,在 4 位具有庞大的烷基取代基得到相应的 N-酰基-α-氨基酸酯。在 4 位取代基较小的情况下(Me,MeOCH2),三苯基鏻基团被甲氧基竞争性取代。在不存在 DBU 的情况下,在仅 150% 过量的 i-PrOH 存在下,在 CH2Cl2 中进行加氢脱膦可以避免后一反应。讨论了加氢脱膦酸化的可能机制。