title: Stereoselective formation of eight-membered rings by radical cyclization of silylenedioxy-tethered bis-methacrylate derivatives.
abstract: Radical-initiated addition of CCl4, Cl3CBr, PhSH, and (TMS)3SiH to (bisisopropyl)silylenedioxy-tethered bis-methacrylate derivatives gives the corresponding eight-membered ring cyclic adducts stereoselectively. Hydrolysis of halo-substituted cyclic adducts with HCl in methanol affords the corresponding valerolactones, and the stereochemistry was determined by the X-ray crystallography on a dibromobenzoate derivative. DFT calculation on the eight-membered radical intermediate offers a plausible rationale for the stereoselectivity of the reaction.
authors: Key Laboratory of Organosilicon Chemistry and Technology, Hangzhou Normal University , Hangzhou, Zhejiang 310036, China.
authors: Fan-Yi
authors: FY
authors: Meng
authors: Shou-Ling
authors: SL
authors: Huang
authors: Yi-Hung
authors: YH
authors: Liu
authors: Ziqiang
authors: Z
authors: Hu
authors: Guoqiao
authors: G
authors: Lai
authors: Tien-Yau
authors: TY
authors: Luh