Direct Catalytic Asymmetric Mannich Reaction with Dithiomalonates as Excellent Mannich Donors: Organocatalytic Synthesis of (<i>R</i>)-Sitagliptin
作者:Han Yong Bae、Mun Jong Kim、Jae Hun Sim、Choong Eui Song
DOI:10.1002/anie.201605167
日期:2016.8.26
enantioselectivity (up to 99 % ee). Furthermore, by the use of a DTM, even some highly challenging primary alkyl α‐amidosulfones were smoothly converted into the desired adducts with excellent enantioselectivity (up to 97 % ee), whereas the use of a malonate or monothiomalonate resulted in no reaction under identical conditions. The synthetic utility of the chiral Mannich adducts obtained from primary alkyl substrates
在这项研究中,二硫代丙二酸酯(DTMs)被证明是在金鸡纳酸-二甲基酰胺催化的各种亚胺或α-酰胺基砜作为亚胺替代物的对映选择性曼尼希反应中的反应活性和立体选择性方面,是曼尼希高效供体。由于与传统丙二酸酯相比,DTM具有更高的反应活性,催化剂负载量可以降低至0.1 mol%,而不会损害对映选择性(最高ee达99% )。此外,通过使用DTM,即使是一些极富挑战性的伯烷基α-酰胺基砜也能以出色的对映选择性(高达ee高达97%)平稳地转化为所需的加合物。 ),而丙二酸酯或一硫代丙二酸酯的使用在相同条件下不会导致反应。从一级烷基底物获得的手性曼尼希加合物的合成效用通过抗糖尿病药(-)-(R)-西他列汀的有机催化,无偶联剂-无合成得到了强调。