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Lin Pu

Publications and source records attributed to Lin Pu.

24 records · Page 2Linked to original sources
PubMed2002

BINOL-catalyzed highly enantioselective terminal alkyne additions to aromatic aldehydes.

[reaction: see text] The readily available BINOL ligand in combination with Ti(O(i)Pr)(4) was found to catalyze the highly enantioselective reaction (92-98% ee) of terminal alkynes with aromatic aldehydes that contain a variety of substituents and substitution patterns. After the preparation of the zinc acetylide reagent, the catalytic asymmetric addition to aldehydes proceeded at room temperature with excellent stereocontrol. This simple catalyst system is practical for the asymmetric synthesis of chiral propargylic alcohols.

Azetidines↗
PubMed2002

A practical enantioselective fluorescent sensor for mandelic acid.

A novel optically active bisbinaphthyl fluorescent sensor, (S,S)- or (R,R)-1, is designed for the recognition of chiral alpha-hydroxycarboxylic acids. A convenient method has been developed to synthesize this compound. It is observed that (S)-mandelic acid enhances the fluorescence intensity of the (S,S)-sensor significantly more than (R)-mandelic acid does. The enantioselective fluorescent response is confirmed with the observation of a mirror image relationship for the interaction of (S,S)- and (R,R)-sensors with mandelic acid. The enantioselectivity in fluorescence response [(I(S) - I(0))/(I(R) - I(0)) = 2.49] is quite high, which makes the sensor useful for practical application. The fluorescence intensity change of the sensor is found to be linearly related to the enantiomeric composition of mandelic acid. This sensor is potentially useful for the combinatorial search of chiral catalysts for the asymmetric synthesis of alpha-hydroxycarboxylic acids.

Fluorescence↗
PubMed1999

Asymmetric Epoxidation of alpha,beta-Unsaturated Ketones Catalyzed by Chiral Polybinaphthyl Zinc Complexes: Greatly Enhanced Enantioselectivity by a Cooperation of the Catalytic Sites in a Polymer Chain.

Polybinaphthyl zinc catalysts have been developed for the asymmetric epoxidation of alpha,beta-unsaturated ketones in the presence of tert-butyl hydroperoxide. Up to 81% ee has been achieved for the epoxidation of alpha,beta-unsaturated ketones containing beta-aliphatic substituents by using a binaphthyl polymer combined with diethylzinc. A very interesting positive cooperative effect of the catalytic sites in the polymer chain is observed which leads to greatly increased enantioselectivity over the corresponding monomer ligands.

Journal Article↗