CHEMISTRY OF PI-COMPLEXES DERIVED FROM [(PH3P)2PT-(ETA-3-CH2CCPH)](O3SCF3) - INTERCONVERSION BETWEEN ETA-3-ALKOXOALLYL AND ETA-3-OXOALLYL COMPLEXES AND BETWEEN ETA-3-AMINOALLYL AND ETA-IMINOALLYL COMPLEXES
Mw. Baize et al., CHEMISTRY OF PI-COMPLEXES DERIVED FROM [(PH3P)2PT-(ETA-3-CH2CCPH)](O3SCF3) - INTERCONVERSION BETWEEN ETA-3-ALKOXOALLYL AND ETA-3-OXOALLYL COMPLEXES AND BETWEEN ETA-3-AMINOALLYL AND ETA-IMINOALLYL COMPLEXES, Inorganica Chimica Acta, 223(1-2), 1994, pp. 1-4
The eta3-alkoxoallyl complexes of platinum (2a-c: R = Me (a), Et (b),
i-Pr (c)) derived from [(Ph3P)2Pt(eta3-CH2CCPh)]+ (1) and ROH are deal
kylated by OMe- to form the eta3-oxoallyl complex (Ph3P)2Pt(eta3-CH2C(
O)CHPh) (3). Reactions of 3 with Et3O+ and (MeO)2SO2 regenerate the et
a3-alkoxoallyl complexes 2a,b. Treatment of 1 with H2O affords binucle
ar [((Ph3P)2Pt(eta3-(CH2)(CHPh)C))2O]2+ (4), which is converted to 3 u
pon treatment with two equivalents of OMe-. The eta3-aminoallyl comple
xes [(Ph3P)2Pt(eta3-CH2C(NHR)CHPh)]+ (6), obtained from 1 and RNH2 (R
= p-MeC6H4NH2, p-O2NC6H4NH2), react with LiPh to afford the eta3-imino
allyl complexes (Ph3P)2Pt(eta3-CH2C(NR)CHPh) (7). Complexes 7 are prot
onated by HBF4 and alkylated by (MeO)2SO2 to yield 6 and [(Ph3P)2Pt(et
a3-CH2C(NRMe)CHPh)]+ (8), respectively. The complex [(Ph3P)2Pt(eta3-CH
2C(NMe2)-CHPh)]+ (5) undergoes fluxional behavior at ambient temperatu
res in solution, and this behavior is ascribed to rotation about the C
=NMe2 bond. The reported chemistry is rationalized by eta3-allyl and m
etallacyclic resonance hybrid properties of 2-8.