MULTIDIMENSIONAL AG-109, P-31, AND H-1 HMQC AND HSQC NMR-STUDIES ON AMODEL HOMOGENEOUS CATALYST - REACTIONS OF A CHIRAL FERROCENYLPHOSPHINE WITH AG(CF3SO3)
F. Lianza et al., MULTIDIMENSIONAL AG-109, P-31, AND H-1 HMQC AND HSQC NMR-STUDIES ON AMODEL HOMOGENEOUS CATALYST - REACTIONS OF A CHIRAL FERROCENYLPHOSPHINE WITH AG(CF3SO3), Inorganic chemistry, 33(22), 1994, pp. 4999-5002
The chiral ferrocene ligand Fe{1-(PPh(2))-2-((R)-CH(Me)N(Me)CH(2)CH(2)
NMe(2))- C5H3}{C(5)H(4)PPh(2)}, 1, reacts with Ag(CF3SO3) to form a tr
inuclear complex Ag-3(1)(2)(CF3SO3)(3), 3, in which there are two diff
erent silver coordination spheres. In one environment two silver catio
ns complex-to the 1-PPh(2) P atom and the two N atoms of the side chai
n, from two ligands 1, whereas the third silver cation coordinates to
two P atoms from two C(5)H(4)PPh(2) moieties. Reaction of 3 with a 70-
fold excess of the isonitrile CNCH(2)CO(2)Me, 4, affords a mononuclear
complex, 5, in which both P atoms of 1 chelate to silver(I). The numb
er of coordinated P-31 spins for 3 and 5 and the coordination of the c
hiral side chain in 3 were determined using HSQC and HMQC Ag-109-P-31,
Ag-109-H-1, and P-31-H-1 multidimensional methods. The relevance of t
hese observations to the Au(I)-catalyzed aldol condensation of aldehyd
es with isonitriles is discussed.