An enantioselective strategy for the synthesis of (S)-tylophorine via one-pot intramolecular Schmidt/Bischler-Napieralski/imine-reduction cascade sequence.
A novel enantioselective strategy for the total synthesis of (S)-tylophorine was developed in an overall yield of 48% with more than 99% ee from readily avaliable azido acid and phenanthryl alcohol. This route features an Evans stereoselective alkylation and an unprecedented one-pot intramolecular Schmidt/Bischler-Napieralski/imine-reduction cascade sequence, in which three new bonds and two rings formed in 84% yield. The intramolecular Schmidt rearrangement of the azido aldehyde was proved to be racemization-free.
State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People's Republic of China.
Bo
B
Su
Fazhong
F
Chen
Qingmin
Q
Wang
D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry*; D000478:Alkylation; D001386:Azides / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D007212:Indolizines / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D010616:Phenanthrenes / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism
D000470:Alkaloids; D001386:Azides; D007097:Imines; D007212:Indolizines; D010616:Phenanthrenes; C004218:tylophorine