Reactions of the Dirhenium(II) Complexes Re(2)X(4)(&mgr;-dppm)(2) (X = Cl, Br; dppm = Ph(2)PCH(2)PPh(2)) with Isocyanides. 19.(1) Studies of the Reactions of Five Structural Isomers of Re(2)Cl(2)(&mgr;-dppm)(2)(CO)(CNXyl)(3) That Lead to the Dirhenium(I) Complexes [Re(2)(&mgr;-Cl)(&mgr;-CO)(&mgr;-dppm)(2)(CNXyl)(4)]O(3)SCF(3) and [Re(2)Cl(&mgr;-dppm)(2)(CO)(CNXyl)(3)(NCCH(3))]O(3)SCF(3).
Three of the five known isomers of Re(2)Cl(2)(&mgr;-dppm)(2)(CO)(CNXyl)(3) (labeled 4' '-8' ' in accord with earlier work) react with 1 equiv each of XylNC and TlO(3)SCF(3) in benzene to produce the symmetrical dirhenium(I) complex [Re(2)(&mgr;-Cl)(&mgr;-CO)(&mgr;-dppm)(2)(CNXyl)(4)]O(3)SCF(3) (I) in good yield. Isomers 4' ', 6' ', and 8' ' are converted to I, while 5' ' gives an unidentified mixture and isomer 7' ' is unreactive. When the reactions of 4' ', 5' ', 6' ', and 8' ' with TlO(3)SCF(3) are carried out in acetonitrile in the absence of XylNC, the compound [Re(2)Cl(&mgr;-dppm)(2)(CO)(CNXyl)(3)(NCCH(3))]O(3)SCF(3) can be isolated in three stable isomeric forms (A-C). Isomer B is unreactive, while A and C react with XylNC in benzene to afford I. Single-crystal X-ray structure determinations have been carried out on compounds I and B.
Ding
Yan
Y
Department of Chemistry, Purdue University, 1393 Brown Building, West Lafayette, Indiana 47907-1393.
Fanwick
Phillip E.
PE
Walton
Richard A.
RA