Reactions of platinum (II)-alkyne and -alkynyl complexes with the hydroxy compounds HO(CH2)2X (X = Br, I, OH)

Article abstract of DOI:10.1016/s0020-1693(98)00149-2

The cationic solvento species trans-[Pt(Me) (PPh₃)₂(solv)] [BF₄] (solv = CH₂Cl₂, Et₂O) reacts with 1.5 equiv. of p-tolylacetylene in the presence of a 10-fold excess of the hydroxylated compounds HOCH₂CH₂X (X = Br, I, OH) to give the corresponding (alkoxy)alkyl carbene complexes frans-[Pt(Me) {=C(OCH₂CH₂X)CH₂(p-tolyl)}(PPh ₃)₂] [BF₄] (1-3). Complexes 1-3 were also obtained by reaction of the acetylide complex trans-[Pt(Me) (C≡CR) (PPh₃)₂] (R=p-tolyl) in the presence of 1 equiv. of HBF₄ with an excess of HOCH₂CH₂X. The carbene complex trans-[Pt(Me) {=C(OCH₂CH₂Cl)CH₂R}(PPh₃) ₂][BF₄] (R = p-tolyl) can be readily deprotonated by NEt₃ to afford the vinyl complex trans-[Pt(Me) {C(OCH₂CH₂Cl)=CH(R)}(PPh₃)₂] (4). A similar behavior is observed also for 1-3 when treated with a base.