There are many protocols for the preparation of hydroxamicacidsfrom their corresponding carboxylic esters or carboxylic acids, but as for ester precursors, strong bases are usually indispensable. Herein, an environmentally benign and scalable protocol was developed to prepare hydroxamicacidsfrom their ester precursors in deep eutectic solvents (DESs). The distinguishing features of this method
从相应的羧酸酯或羧酸制备异羟肟酸的方案有很多,但对于酯前体,强碱通常是必不可少的。在此,开发了一种环境友好且可扩展的协议,以在低共熔溶剂(DES)中从其酯前体制备异羟肟酸。该方法的显着特点是无碱过程和氧化锌的促进,这也促进了产品的分离与其螯合形成沉淀。后处理被设计为产品纯化和试剂回收的集成解决方案,提高了资源效率并降低了 PMI 和 WI。各种异羟肟酸,包括对映体纯异羟肟酸,通过该协议以良好到极好的收率制备,并且氧化锌和 DESs 的可回收性通过至少连续四次连续运行的克规模制备伏立诺他得到证明。
Angelico; Fanara, Gazzetta Chimica Italiana, 1901, vol. 31 II, p. 31
作者:Angelico、Fanara
DOI:——
日期:——
Consecutive Lossen rearrangement/transamidation reaction of hydroxamic acids under catalyst- and additive-free conditions
The Lossenrearrangement is a classic process for transforming activated hydroxamic acids into isocyanate under basic or thermal conditions. In the current report we disclosed a consecutive Lossenrearrangement/transamidation reaction in which unactivated hydroxamic acids were converted into N-substituted formamides in a one-pot manner under catalyst- and additive-free conditions. One feature of this