- One step synthesis of optically active diazabicyclo-[3.3.0] octanones or diazabicyclo [4.3.0] nonanones by asymmetric conjugate addition of cyclic hydrazine
-
Asymmetric conjugate addition-cyclization of lithium amide of 6-membered hydrazine 4, piperidazine, (or 5-membered hydrazine 6, pyrazolidine) to N-(E)-cinnamoyl-(1S)-2,10-camphorsultam (1S)-3 afforded β-amino acid derivative (S)-1 {or (S)-2} for the synthesis of polyamine alkaloids in good yield with good stereoselectivity (up to 86% ee).
- Seki, Chigusa,Hirama, Masafumi,Sato, Takeshi,Takeda, Saya,Kohari, Yoshihito,Ishigaki, Kazuhiro,Ohuchi, Masafumi,Yokoi, Kiyoshi,Nakano, Hiroto,Uwai, Koji,Takano, Nobuhiro,Umemura, Kazuyuki,Matsuyama, Haruo
-
experimental part
p. 1045 - 1052
(2012/07/28)
-
- Conjugate addition of 6-membered hydrazine to chiral tert-butyl (E)-2-(p-tolylsulfinyl)cinnamates. Synthesis of (S)-celacinnine
-
Two enantiomers of the bicyclic lactam, (S)- and (R)-9-phenyl-1,6-diazabicyclo[4.3.0]nonan-7-one (6), were synthesized stereoselectively with high optical purity (95% ee) by the asymmetric conjugate addition-cyclization of piperidazine to chiral vinyl sulfoxides, tert-butyl (E)-2-[(R)- and (S)-p-tolylsulfinyl]cinnamate (4), followed by removal of the p-tolylsulfinyl group with SmI2. The subsequent reductive cleavage of the N-N bond of the bicyclic lactam 6 with sodium in liquid ammonia produced the corresponding 9-membered azalactam, (S)- and (R)-4-phenyl-1,5-diazacyclononan-2-one (7) with 99% and 97% ee, respectively. X-ray crystallography showed that (S)-7 exists exclusively as a trans conformer in the crystal state. Starting from (S)-7, naturally occurring (S)-celacinnine 1 was synthesized with 99% ee employing the ring-expansion reaction via intramolecular transamidation.
- Matsuyama,Itoh,Matsumoto,Ohira,Hara,Yoshida,Iyoda
-
p. 2924 - 2930
(2007/10/03)
-
- Chiral vinyl sulfoxides as useful reagents for the synthesis of β-amino acid derivatives
-
(S)- and (R)-β-amino acid derivatives were synthesized by the asymmetric conjugate addition of ammonia and piperidazine to t-butyl (E)-2-[(R)-and (S)-p-tolylsulfinyl]cinnamates, respectively.
- Matsuyama, Haruo,Itoh, Nobuhiro,Yoshida, Masato,Iyoda, Masahiko
-
p. 475 - 476
(2007/10/03)
-
- ASYMMETRIC SYNTHESIS OF CELACINNINE UTILIZING OPTICALLY ACTIVE VINYL SULFOXIDES
-
First asymmetric synthesis of celacinnine (10) was achieved from the nine-membered azalactam, 3-phenyl-4-azaoctanelactam (6), which was synthesized by the addition of piperidazine (4) to optically active vinyl sulfoxides (3).
- Itoh, Nobuhiro,Matsuyama, Haruo,Yoshida, Masato,Kamigata, Nobumasa,Iyoda, Masahiko
-
p. 415 - 418
(2007/10/02)
-
- Diastereoselective Conjugate Addition of Cyclic Hydrazine to Optically Active Vinyl Sulfoxide. A Novel Synthesis of Optically Active Azalactams
-
Optically active (R)-(+)-1,5-diaza-4-phenylbicyclononan-2-one (5) was prepared in high optical purity by diastereoselective conjugate addition of piperidazine to optically active (E)-(S)-1-(methoxycarbonyl)-2-phenylvinyl p-tolyl sulfoxide, followed
- Matsuyama, Haruo,Itoh, Nobuhiro,Kamigata, Nobumasa
-
p. 1547 - 1550
(2007/10/02)
-