Novel stereochemistry, reactivity, and stability of an arsenic heterocycle in a metal-promoted asymmetric cycloaddition reaction

作者：Ma Mengtao; Pullarkat Sumod A; Li Yongxin; Leung Pak Hing^*

来源：Inorganic Chemistry, 2007, 46(22): 9488-9494.

DOI：10.1021/ic701419j

The organopalladium complex containing ortho-metalated (S)-[1-(dimethylamino)ethyl]phenylene as the chiral auxiliary has been used as the chiral template to promote the asymmetric cycloaddition reaction between diphenylvinylphosphine and 3,4-dimethyl-1-phenylarsole. A diphenylphosphino-substituted asymmetrical heterobidentate arsanorbomene (As-P) ligand was obtained stereoselectively on the chiral palladium template in moderate yield. The chiral benzylamine auxiliary could be removed chemoselectively from the template by treatment with HCI to produce the neutral complex [(As-P)PdCl2]- In contrast to their reported P-P analogue, the arsenic donor in the dichloro complex could be eliminated stereospecifically under mild reaction conditions to generate the corresponding 1-(diphenylphosphino)-3,4-dimethyl-2,4-cyclohexadiene, which remained as a bidentate ligand at the PdCl2 unit via phosphorus and the n(2)-C-4-C-5 double bond. The arsenic-elimination process was found to be influenced by the halo ligand in [(As-P)PdX2]. A similar process was observed with the analogous dibromo complex, but the corresponding diiodo species did not show similar reactivity. All of the novel As-Pd complexes have been characterized by X-ray crystallography.

• 出版日期2007-10-29
• 单位南阳理工学院