Design and Development of Pd-Catalyzed Aerobic<i>N</i>-Demethylation Strategies for the Synthesis of Noroxymorphone in Continuous Flow Mode
作者:Bernhard Gutmann、David Cantillo、Ulrich Weigl、D. Phillip Cox、C. Oliver Kappe
DOI:10.1002/ejoc.201601453
日期:2017.1.26
opiates and a double bond hydrogenation. The pivotal reaction step thereby is a N-methyl oxidation with colloidal palladium(0) as catalyst and pure oxygen as terminal oxidant. The reaction produces a 1,3-oxazolidine intermediate, which can be readily hydrolyzed to the corresponding secondary amine. Different reaction sequences and various phenol protection groups were explored. The most direct route consumes
介绍了从 14-羟基吗啡酮生成去甲羟吗啡酮的策略。去甲羟吗啡酮是合成各种阿片类拮抗剂(包括纳洛酮、纳曲酮和纳美芬)以及混合激动剂-拮抗剂(如纳布啡)的关键中间体。转化需要从天然存在的鸦片制剂中去除 N-甲基基团并进行双键氢化。因此,关键的反应步骤是用胶体钯 (0) 作为催化剂和纯氧作为末端氧化剂的 N-甲基氧化。该反应生成 1,3-恶唑烷中间体,它可以很容易地水解成相应的仲胺。探索了不同的反应顺序和各种酚保护基团。最直接的途径仅消耗 H2、O2 和 H2O 作为化学计量试剂,仅产生 H2O 作为副产品。