1. Asymmetric Diels–Alder reaction between 3,4-dimethyl-1-phenylphosphole and (Z/E)-diphenyl-1-styrylphosphine
- Author
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Weiwei Yao, Pak-Hing Leung, Jia Li, Mengtao Ma, and Xingchao Shen
- Subjects
Chiral auxiliary ,010405 organic chemistry ,Stereochemistry ,Organic Chemistry ,Diastereomer ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Medicinal chemistry ,Cycloaddition ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Naphthylamine ,chemistry ,Yield (chemistry) ,Organopalladium ,Materials Chemistry ,Stereoselectivity ,Physical and Theoretical Chemistry ,Diels–Alder reaction - Abstract
The organopalladium complex containing ortho-metalated (S)-[1-(dimethylamino)ethyl]naphthalene as the chiral auxiliary has been successfully employed to promote the asymmetric Diels–Alder reaction between 3,4-dimethyl-1-phenylphosphole and (Z)-diphenyl-1-styrylphosphine or (E)-diphenyl-1-styrylphosphine. In the intramolecular cycloaddition reaction between (E)-diphenyl-1-styrylphosphine and 3,4-dimethyl-1-phenylphosphole, a pair of diastereomeric endo-cycloadducts were obtained in the ratio of 1:1. However, the asymmetric reaction between (Z)-diphenyl-1-styrylphosphine and 3,4-dimethyl-1-phenylphosphole also produced the same endo-product in the same stereoselectivity unexpectedly. The chiral naphthylamine auxiliary could be removed chemoselectively from the template by treatment with concentrated hydrochloric acid to generate the neutral stable dichloro complex [(P–P)PdCl2]. Treatment of the dichloro complex with KCN gave the pure bis-phosphine ligand in quantitative yield.
- Published
- 2016