Highly enantioselective diethylzinc addition to imines employing readily available N-monosubstituted amino alcohols.
An easily accessible chiral ligand 3c, which promoted diethylzinc addition to imines with 96-98% ee, has been found by finely screening N,N-disubstituted and N-monosubstituted amino alcohols. N-monosubstituted amino alcohols, on average, gave slightly higher enantioselectivities than their N,N-disubstituted analogues. These results imply that the restricted and rigid structure of amino alcohol is not the absolute requirement for the highly enantioselective dialkylzinc addition to diphenylphosphinoylimines. [structure: see text]
Zhang
Hai-Le
HL
Union Laboratory of Asymmetric Synthesis, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China.
Zhang
Xiao-Mei
XM
Gong
Liu-Zhu
LZ
Mi
Ai-Qiao
AQ
Cui
Xin
X
Jiang
Yao-Zhong
YZ
Choi
Michael C K
MC
Chan
Albert S C
AS
D000605:Amino Alcohols / Q000737:chemistry*; D007097:Imines / Q000138:chemical synthesis*; D008024:Ligands; D009942:Organometallic Compounds / Q000737:chemistry*; D013237:Stereoisomerism; D015032:Zinc / Q000737:chemistry*
D000605:Amino Alcohols; D007097:Imines; D008024:Ligands; D009942:Organometallic Compounds; D015032:Zinc; C454811:diethylzinc