Palladium-Catalyzed Reaction of Diselenide with Isocyanide
1998; American Chemical Society; Volume: 17; Issue: 5 Linguagem: Inglês
10.1021/om970936p
ISSN1520-6041
AutoresHitoshi Kuniyasu, Akitugu Maruyama, Hideo Kurosawa,
Tópico(s)Metal complexes synthesis and properties
ResumoA Pd-catalyzed reaction providing the first example of insertion of isocyanide into a Pd−Se bond is described. Tetrakis(triphenylphosphine)palladium [Pd(PPh3)4] catalyzes the reaction of a diselenide (ArSe)2 (1a) with an isocyanide ArNC (2) (Ar = 4-MeC6H4) to afford the adducts (ArSe)(CNAr)m(SeAr) (m = 2, 3). An X-ray crystallographic structure of the palladium intermediate trans-Pd(SeAr)2(CNAr)(PPh3) (7a) is determined. In marked contrast to the Pd-catalyzed reaction using a disulfide, the 1:1-adduct 3a (m = 1) is not produced. The stoichiometric reaction of 7a with 1a also did not provide 3a. These facts suggest that the reductive elimination of 1:m-adducts takes place only when more than two isocyanides are inserted into Pd−Se bond(s) of 7a to give Pd[(CNAr)p(SeAr)][(CNAr)q(SeAr)]Ln (p, q ≥ 0) (10a). In contrast, the reaction of ditelluride (PhTe)2 (1c) with 2 is not catalyzed by the Pd complex due in part to the insolubility and instability of the palladium(II) tellurolate intermediates.
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