Hydrolytic enantioselective protonation, 2-isopropyl-5-methylcyclohexa-1,5-dien-1-yl 2-chloroacetate, (R)-6-isopropyl-3-methylcyclohex-2-en-1-one, (8α,9R)- 1-(9-anthracenylmethyl)- 9-hydroxy-Cinchonanium chloride, Cinchonidine Derivative
alpha-Alkylation, 5-methoxy-1,3-dimethylindolin-2-one, 2-chloroacetonitrile, (S)-2-(5-methoxy-1,3-dimethyl-2-oxoindolin-3-yl)acetonitrile, (1S,2R,4S,5R)-1-(2,3-dichlorobenzyl)-2-((S)-hydroxy(quinolin-4-yl)methyl)-5-vinylquinuclidin-1-ium chloride, Cinchonine Derivative
Cyclization, isopropyl (E)-2-(2-(benzylideneamino)phenyl)-2-phenylacetate, isopropyl (2R,3R)-2,3-diphenylindoline-3-carboxylate, isopropyl (2R,3S)-2,3-diphenylindoline-3-carboxylate, (8α,9R)-9-hydroxy-1-(phenylmethyl)-Cinchonanium chloride, Cinchonidine Derivative
Aldol reaction, aldehydes, cyclohexanone, (S)-2-((R)-hydroxy-substituted-methyl)cyclohexan-1-one, Chitosan-supported cinchonine, Cinchonine Derivative
alpha-Chlorination, methyl 4-bromo-1-oxo-2,3-dihydro-1H-indene-2-carboxylate, chlorosuccinimide, methyl (R)-4-bromo-2-chloro-1-oxo-2,3-dihydro-1H-indene-2-carboxylate, 1-[2-([1,1′-biphenyl]-2-ylamino)-2-oxoethyl]-9-hydroxy-6′-methoxy-(8α,9R)-Cinchonanium bromide (1:1), Quinine Derivative
Aza-Henry, disubstituted (E)-(phenyl(tosylimino)methyl)phosphonate, nitromethane, disubstituted (R)-(1-((4-methylphenyl)sulfonamido)-2-nitro-1-phenylethyl)phosphonate, N-[3,5-Bis(trifluoromethyl)phenyl]-N′-(9S)-cinchonan-9-ylthiourea, Cinchonine Derivative
alpha-Bromination, acid chlorides, 2,2,4,7-tetrabromonaphthalen-1(2H)-one, 2,4,7-tribromonaphthalen-1-yl 2-substituted-2-bromoacetates, 6′-methoxy-(8α,9R)-Cinchonan-9-ol 9-[1-(1,1-dimethylethyl) (2R)-1,2-pyrrolidinedicarboxylate], Quinine Derivative
The optimization of a practical, catalytic, asymmetric process for the α-bromination of acid chlorides to produce synthetically versatile, optically active α-bromoesters is reported. A range of products is produced in high enantioselectivity and moderate to good chemical yields with retention of both upon scale-up. The reactions herein are catalyzed by cinchona alkaloid derivatives, with the best performance achieved by the use of a proline cinchona alkaloid conjugate designed in a de novo fashion.