Helix-Sense-Selective and Enantiomer-Selective Living Polymerization of Phenyl Isocyanide Induced by Reusable Chiral Lactide Using Achiral Palladium Initiator

• DOI: 10.1021/acs.macromol.5b02124
• Publication Date: 2015-10-28T16:22:13Z
• Authors: Jia-Li Chen; Li Yang; Qian Wang; Zhi-Qiang Jiang; Na Liu; Jun Yin; Yunsheng Ding; Zong-Quan Wu
• Keywords: Chirality; Helix (gastropod); Enantiomeric excess; Asymmetric induction; Lactide

Polymerization of phenyl isocyanide using achiral Pd(II) initiator with the presence chiral l- or d-lactide (l-LA d-LA) as additive was found to proceed in helix-sense-selective manner. The polymerization isocyanide, 4-isocyanobenzoyl-2-aminoisobutyric acid decyl ester (1) by this method produced optically active helical poly-1m(L), whose chirality solely come from conformation without containing any other atoms. added LA can be facilely recovered and reused polymerizations significantly loss its induction, economy is high. When enantiomerically pure bearing an R- S-alanine pendent a long n-decyl chain (1r 1s) were polymerized method, highly enantiomer-selective manner one enantiomers preferentially over antipode factor 3.6. Single-handed polyisocyanides achieved when monomer appropriately matched LA.