A highlyenantioselective addition of alcohols to cyclic trifluoromethyl ketimines is developed catalyzed by quinine-thiourea, giving biologically interesting N,O-ketals in up to 99% yield and 96% ee.
Mannich reactions of aldehydes with ketimines is exemplified by isatin‐derived ketimines and cyclic trifluoromethyl ketimines. Primary amine catalysts exhibit either unusual stereoselectivity or reactivity, which is not observable with secondary amine catalysts. Moreover, reversal of diastereofacial selectivity between primary and secondary amine catalysts is disclosed. These new reactions provide
Quinine-thiourea catalyzed enantioselective hydrophosphonylation of trifluoromethyl 2(1H)-quinazolinones
作者:Hexin Xie、Aiguo Song、Xinshuai Zhang、Xiaobei Chen、Hao Li、Chunquan Sheng、Wei Wang
DOI:10.1039/c2cc38097h
日期:——
An organocatalytic enantioselective addition reaction of cyclic ketoimines with phosphites has been developed for the first time. The process, catalyzed by Soós' quinine thiourea, affords synthetically and medicinally interesting enantioenriched trifluoromethyl dihydroquinazolinones in high yields and with high enantioselectivities.
Hydrogen-Bond-Directed Enantioselective Decarboxylative Mannich Reaction of β-Ketoacids with Ketimines: Application to the Synthesis of Anti-HIV Drug DPC 083
作者:Hai-Na Yuan、Shuai Wang、Jing Nie、Wei Meng、Qingwei Yao、Jun-An Ma
DOI:10.1002/anie.201210361
日期:2013.4.2
Key to success: The title reaction provides facile access to enantioenriched 3,4‐dihydroquinazolin‐2(1H)‐ones containing a quaternary stereogenic center in high yields with excellent enantioselectivities. Subsequent transformations lead to the convenient preparation of the anti‐HIV drug DPC 083 and N‐fused polycyclic compounds without loss of enantiomeric excess.
Highly Enantioselective Decarboxylative Mannich Reaction of Malonic Acid Half Oxyesters with Cyclic Trifluoromethyl Ketimines: Synthesis of β-Amino Esters and Anti-HIV Drug DPC 083
作者:Hai-Na Yuan、Shen Li、Jing Nie、Yan Zheng、Jun-An Ma
DOI:10.1002/chem.201303307
日期:2013.11.18
An organocatalyticenantioselectivedecarboxylative Mannich reaction of malonicacidhalf oxyesters with cyclic ketimines was developed for the preparation of enantioenriched β‐amino esters with a quaternary stereogenic center and the anti‐HIV drug DPC 083 (see scheme).