220943-78-2Relevant academic research and scientific papers
High reactivity of (P,N)Pd(methyl)+ derivatives toward mixtures of CO and norbornene
Luinstra, Gerrit A.
, p. 5160 - 5165 (2008/10/08)
The reactivity of cationic (P,N)PdMe(CO)+ (P,N = Ph2P-o-C6H4CH2NMe2, Me2N-o-C6H4-CH2PPh2, 1-(dimethylamino)-8-(diphenylphosphino)naphthalene; anion, -B[3,5-Ph(CF3)2]4) toward CO and norbornene is described. CO and norbornene insert slowly into the palladium-methyl bond to yield (P,N)Pd[C(O)Me]+ and [-3-methyl-2-norbornyl]+ derivatives. Compounds (P,N)PdMe(CO)+ react fast with mixtures of CO and norbornene under formation of (P,N)Pd[C7H10C(O)Me]+ and two isomers of (P,N)Pd[C7H10C(O)C7H10Me] +. The dissimilarity in rates is explained in a kinetic model, wherein reactive intermediates are reversibly formed and trapped by norbornene in case of trans-P (P,N)Pd[C(O)Me]+ and CO in case of trans-P (P,N)Pd(C7H10Me)+ complexes. CO insertion into the Pd-alkyl bond takes place in the trans-N Pd-alkyl complexes, and norbornene inserts into the Pd-acyl bond from the trans-P Pd-acyl complexes. Isomerization from trans-P to trans-N in (P,N)Pd[C(O)Me]+ is slow with respect to CO deinsertion and subsequent norbornene insertion into the trans-P (P,N)Pd+-acyl bond. Fast and reversible trans-N-to-P isomerization is found in compounds (P,N)Pd[C(O)-3-Me-2-C7H10]+.
