Radical Cyclization in Heterocycle Synthesis. 6.(1) A New Entry to Cyclic Amino Alcohols via Stannyl Radical Cyclization of Oxime Ethers Connected with Aldehydes or Ketones.
Oxime ethers connected by a tether to aldehydes or ketones efficiently cyclize via stannyl radical addition-cyclization to provide a new entry to cyclic amino alcohols. Upon treatment with tributyltin hydride in the presence of AIBN, oxime ethers connected with either an aldehyde or a ketone via a nitrogen atom smoothly underwent stannyl radical addition-cyclization to give five- to seven-membered cis- and trans-heterocyclic amino alcohols of which the trans-isomers were major products. The newly found radical cyclization provides a novel method for preparing not only bifunctionalized heterocyclic compounds but also adjacently functionalized amino alcohols carrying two quaternary carbons.
Naito
Takeaki
T
Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan.
Nakagawa
Kazumi
K
Nakamura
Takako
T
Kasei
Akira
A
Ninomiya
Ichiya
I
Kiguchi
Toshiko
T