发现富含地球的镍与合适的手性双膦配体配合使用,是2-酰胺基丙烯酸酯不对称氢化的有效催化剂,以定量收率和优异的对映选择性(高达96%ee)提供了手性α-氨基酸酯。通过NMR和HRMS对活性催化剂组分进行了研究,这有助于我们以克级实现高催化效率且催化剂负载量低(S / C = 2000)。氢化产物可以简单地转化为手性α-氨基酸,β-氨基醇及其生物活性衍生物。此外,使用氘标记实验和计算计算研究了催化机理。
Cross-Coupling of Cyclobutenone <i>N</i>-Tosylhydrazones with Organohalides: Access to Conjugated Enynes and Enallenes via a Strained Allylpalladium Intermediate
palladium-catalyzed cross-couplingreaction of cyclobutenone N-tosylhadrazones with organohalides is disclosed. The protocol involves the generation of a strained allylpalladium intermediate from readily available starting materials through palladium carbene migratory insertion, which undergoes electrocyclic ring opening and β-hydride elimination for the production of conjugated enynes and enallenes