Reactions of the haloalcohols HO(CH 2) nCl ( n = 2, 3) with platinum(II) - alkynyl and -alkyne complexes. X-ray crystal structure of trans-[Pt(Me) {C(OCH 2CH 2Cl) (CH 2Ph)} (PPh 3) 2] [BF 4

Abstract

The chloro complexes trans-[Pt(Me)(Cl)(PPh 3) 2], after treatment with AgBF 4, react with 1-alkynes HCCR in the presence of NEt 3 to afford the corresponding acetylide derivatives trans-[Pt(Me) (CCR) (PPh 3) 2] (R = p-tolyl ( 1), Ph ( 2), C(CH 3) 3 ( 3)). These complexes, with the exception of the t-butylacetylide complex, react with the chloroalcohols HO(CH 2) n Cl ( n = 2, 3) in the presence of 1 equiv. of HBF 4 to afford the alkyl(chloroalkoxy)carbene complexes trans-[Pt(Me) {C[O(CH 2) n Cl](CH 2R) } (PPh 3) 2][BF 4] ( R = p- tolyl, n = 2 ( 4), n = 3 ( 5); RPh, n = 2 ( 6) ). A similar reaction of the bis(acetylide) complex trans-[Pt(CCPh) 2(PMe 2Ph) 2] with 2 equiv. HBF 4 and 3-chloro-1-propanol affords trans-[Pt(CCPh) {C(OCH 2CH 2CH 2Cl)(CH 2Ph) } (PMe 2Ph) 2][BF 4] ( 7). T alkyl(chloroalkoxy)-carbene complex trans-[Pt(Me) {C(OCH 2CH 2Cl)(CH 2Ph) } (PPh 3) 2][BF 4] ( 8) is formed by reaction of trans-[Pt(Me)(Cl)(PPh 3) 2], after treatment with AgBF 4 in HOCH 2CH 2Cl, with phenylacetylene in the presence of 1 equiv. of n-BuLi. The reaction of the dimer [Pt(Cl)(μ-Cl)(PMe 2Ph)] 2 with p-tolylacetylene and 3-chloro-1-propanol yields cis-[ PtCl 2{ C(OCH 2 CH 2 CH 2 Cl)( CH 2 C 6 H 4-p- Me}( PMe 2 Ph)] ( 9) . The X-ray molecular structure of ( 8) has been determined. It crystallizes in the orthorhombic system, space group Pna2 1, with a = 11.785(2), b = 29.418(4), c = 15.409(3) A ̊ , V = 4889(1) A ̊ 3 and Z = 4 . The carbene ligand is perpendicular to the Pt(II) coordination plane; the PtC(carbene) bond distance is 2.01(1) Å and the short C(carbene)-O bond distance of 1.30(1) Å suggests extensive electronic delocalization within the PtC(carbene)O moietry.