3-Hydroxypyrroles and 1H-pyrrol-3(2H)-ones. Part 2. Scope and limitations of the synthesis of pyrrol-3-ones by pyrolysis of aminomethylene Meldrum's acid derivatives
作者:Hamish McNab、Lilian C. Monahan
DOI:10.1039/p19880000863
日期:——
Flash vacuum pyrolysis of N,N-disubstituted aminomethylene Meldrum's acid derivatives provides a route to 4,5-unsubstituted 1H-pyrrol-3(2H)-ones by a hydrogen-transfer–cyclisation sequence. Alkyl and aryl 1-substituted, 1,2-disubstituted, and 1,2,2-trisubstituted pyrrolones can be obtained. In competitive cases, there is little selectivity between hydrogen transfer from primary, secondary, or tertiary
N,N-二取代的氨基亚甲基Meldrum的酸衍生物的快速真空热解通过氢转移-环化序列提供了通往4,5-未取代的1 H-吡咯-3(2 H)-ones的途径。可以获得烷基和芳基的1-取代的,1,2-二取代的和1,2,2-三取代的吡咯烷酮。在竞争性情况下,尽管苄基氢原子被证明具有特别的反应性,但从伯,仲或叔位转移的氢之间几乎没有选择性,从而可以合成2-苯基-1 H-吡咯-3(2 H)-。