TY - JOUR
T1 - An enantioselective formal synthesis of 4-demethoxydaunomycin using the catalytic asymmetric ring opening reaction of meso-epoxide with p-anisidine
AU - Sekine, Akihiro
AU - Ohshima, Takashi
AU - Shibasaki, Masakatsu
N1 - Funding Information:
This research was supported by CREST, The Japan Science and Technology Corporation (JST), RFTF of Japan Society for the Promotion of Science, and a Grant-in-Aid for Scientific Research on Priority Areas (A) ‘Exploitation of Multi-Element Cyclic Molecules’ from the ministry of Education, Culture, Sports, Science and Technology, Japan.
PY - 2002/1/1
Y1 - 2002/1/1
N2 - A catalytic asymmetric formal synthesis of 4-demethoxydaunomycin (3) was achieved using a catalytic asymmetric ring opening reaction of meso-epoxide 9 as a key step. The epoxide opening reaction was promoted by 10 mol% of Pr-(R)-BINOL-Ph3P=O complex to give the β-amino alcohol 11 in 80% yield with 65% enantiomeric excess (ee). Single recrystallization enhanced the enantiomeric purity of the β-amino alcohol 11 to 95% ee. The β-amino alcohol 11 was then converted to the known key intermediate 6 through several steps, including a methylation, Hofmann elimination, an oxymercuration, and addition of an ethynyl group in a highly diastereoselective manner.
AB - A catalytic asymmetric formal synthesis of 4-demethoxydaunomycin (3) was achieved using a catalytic asymmetric ring opening reaction of meso-epoxide 9 as a key step. The epoxide opening reaction was promoted by 10 mol% of Pr-(R)-BINOL-Ph3P=O complex to give the β-amino alcohol 11 in 80% yield with 65% enantiomeric excess (ee). Single recrystallization enhanced the enantiomeric purity of the β-amino alcohol 11 to 95% ee. The β-amino alcohol 11 was then converted to the known key intermediate 6 through several steps, including a methylation, Hofmann elimination, an oxymercuration, and addition of an ethynyl group in a highly diastereoselective manner.
UR - http://www.scopus.com/inward/record.url?scp=0036135096&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0036135096&partnerID=8YFLogxK
U2 - 10.1016/S0040-4020(01)01088-2
DO - 10.1016/S0040-4020(01)01088-2
M3 - Article
AN - SCOPUS:0036135096
VL - 58
SP - 75
EP - 82
JO - Tetrahedron
JF - Tetrahedron
SN - 0040-4020
IS - 1
ER -