ISSN:
0268-2605
Keywords:
Alkenes
;
Pt—H insertion
;
platinum hydrides
;
alkyl complexes
;
phosphine complexes
;
31P NMR
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
An interaction of trans-[PtH(SnX3)L2] (I, L = PPh3, PMePh2, PEt3; PBu3; X = Cl, Br) with ethylene, propene and 2-methylpropene has been studied by means of 31P and 1H NMR spectroscopy. The reactions of platinum hydrides I with ethylene are rapid and reversible at -90°C, giving cis-[PtR(SnX3)L2] (II, R = C2H5). The reaction of propene with I (L = PPh3, PMePh2) gives II, R = C3H7. 13C and 1H NMR spectra prove the n-propyl structure for II, L = PMePh2, X = Cl. Complexes II irreversibly isomerize into trans-[PtR(SnX3)L2] between -50° and 0°C. The equilibrium constants and rates are estimated for the reactions of I with alkenes. They decrease as a function of L (PMePh2 〉 PPh3 〉 PBu3 〉 PEt3) and X (Br 〉 Cl). The reactivities of alkenes decrease with increase of steric hindrances at the double bond.
Additional Material:
5 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/aoc.590040205
Permalink
