Liu Lijia, Long Qing, Aoki Toshiki, Zhang Geng, Kaneko Takashi, Teraguchi Masahiro, Zhang Chunhong, Wang Yudan
Polymer Materials Research Center, Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin, China.
Graduate School of Science and Technology, Niigata University, Niigata, Japan.
Chirality. 2015 Aug;27(8):454-8. doi: 10.1002/chir.22455. Epub 2015 May 12.
One-handed helical polyphenylacetylenes having achiral amino alcohol moieties, but no chiral side groups, were synthesized by the helix-sense-selective copolymerization of an achiral phenylacetylene having an amino alcohol side group with a phenylacetylene having two hydroxyl groups. Since the resulting helical copolymers were successfully utilized as chiral ligands for the enantioselective alkylation of benzaldehyde with diethylzinc, we can conclude that the main-chain chirality based on the one-handed helical conformation is useful for the chiral catalysis of an asymmetric reaction for the first time. The enantioselectivities of the reaction were controlled by the optical purities of the helical polymer ligands. In addition, the polymer ligands could be easily recovered by precipitation after the reaction.
通过具有氨基醇侧基的非手性苯乙炔与具有两个羟基的苯乙炔进行螺旋方向选择性共聚，合成了具有非手性氨基醇部分但没有手性侧基的单手螺旋聚苯乙炔。由于所得的螺旋共聚物成功地用作苯甲醛与二乙基锌对映选择性烷基化反应的手性配体，我们首次得出结论，基于单手螺旋构象的主链手性对于不对称反应的手性催化是有用的。该反应的对映选择性由螺旋聚合物配体的光学纯度控制。此外，反应后通过沉淀可以很容易地回收聚合物配体。
