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
Asymmetricarylation of 4‐fluoroalkyl‐2‐quinazolinone derivatives with arylboronic acids proceeded smoothly in the presence of a cationic palladiumcatalyst (1 mol %) coordinated with a chiral phosphinooxazoline (phox) ligand to create the corresponding fluorine‐containing arylated dihydroquinazolinones in high yields and with greater than 99 % ee.
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).
Zinc-mediated enantioselective addition of terminal 3-en-1-ynes to cyclic trifluoromethyl ketimines
作者:Yue Zhang、Jing Nie、Fa-Guang Zhang、Jun-An Ma
DOI:10.1016/j.jfluchem.2018.01.008
日期:2018.4
A facile enantioselectiveaddition of terminal 3-en-1-ynes to cyclic N-acyl trifluoromethyl ketimines is reported. In the presence of Zinc/BINOL complexes, a series of enynylated tertiary carbinamines were readily obtained in 90–97% yield with 70–97% enantiomeric excess in a single chemical operation under mild reaction conditions.