TY - JOUR
T1 - cis- and enantio-selective cyclopropanation with chiral (ON+)Ru-salen complex as a catalyst
AU - Uchida, Tatsuya
AU - Irie, Ryo
AU - Katsuki, Tsutomu
N1 - Funding Information:
Financial supports from a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, Sports, and Culture, Japan, and Asahi glass foundation are gratefully acknowledged.
PY - 2000/5/26
Y1 - 2000/5/26
N2 - Cyclopropanation of styrene with α-diazoacetate in the presence of (R,R)-(salen)ruthenium complex 4 in THF which dissolves the complex exhibits remarkable cis- and enantio-selectivity [cis:trans=97:3, >97% ee (1S,2R)], while the same reaction in hexane which does not dissolve it shows good but opposite sense of enantioselectivity [-83% ee (1R,2S)] together with moderate cis-selectivity (cis:trans=68:32). In homogeneous and heterogeneous conditions, (salen)ruthenium complexes are considered to have different ligand-conformation which, in turn, causes the opposite sense of enantioface selectivity in the cyclopropanation. 2000 Elsevier Science Ltd.
AB - Cyclopropanation of styrene with α-diazoacetate in the presence of (R,R)-(salen)ruthenium complex 4 in THF which dissolves the complex exhibits remarkable cis- and enantio-selectivity [cis:trans=97:3, >97% ee (1S,2R)], while the same reaction in hexane which does not dissolve it shows good but opposite sense of enantioselectivity [-83% ee (1R,2S)] together with moderate cis-selectivity (cis:trans=68:32). In homogeneous and heterogeneous conditions, (salen)ruthenium complexes are considered to have different ligand-conformation which, in turn, causes the opposite sense of enantioface selectivity in the cyclopropanation. 2000 Elsevier Science Ltd.
UR - http://www.scopus.com/inward/record.url?scp=0034717118&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034717118&partnerID=8YFLogxK
U2 - 10.1016/S0040-4020(00)00273-8
DO - 10.1016/S0040-4020(00)00273-8
M3 - Article
AN - SCOPUS:0034717118
SN - 0040-4020
VL - 56
SP - 3501
EP - 3509
JO - Tetrahedron
JF - Tetrahedron
IS - 22
ER -