Me. Elliott et al., Synthesis and study of phosphines incorporating 2-cyanophenyl groups and the X-ray structure of tris(2-cyanophenyl)phosphine, POLYHEDRON, 18(11), 1999, pp. 1603-1608
Both PhP(2-NCC6H4)(2) and P(2-NCC6H4)(3) have been synthesized from the car
banions generated from 2-bromobenzonitrile and dimethyl phenylphosphonite o
r triphenyl phosphite. The A(1) upsilon(CO) bands for the Ni(CO)(3)L comple
xes of these two ligands along with that from the previously reported Ph2P(
2-NCC6H4) have been recorded in dichloromethane solutions. The values (2073
.0, 2076.4 and 2079.7 cm(-1); decreasing number of Ph rings) reflect the el
ectron-withdrawing nature of the ortho-positioned cyano groups. P-31 chemic
al shifts of the L2PdCl2 complexes of these three ligands have been recorde
d, and all provide shifts of delta=24.1+/-1, approximately that for (PPh3)(
2)PdCl2, delta=23.9. The molecular structure of P(2-NCC6H4)(3), from X-ray
crystallographic studies, is reported. A prominent feature of the structure
is that the cyano groups are pointed in the general direction of the phosp
horus lone pair. The average distances from phosphorus to cyano carbon and
nitrogen atoms were found to be 3.03 and 3.23 Angstrom, respectively. (C) 1
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