Reactions of Platinum Terminal Polyynyl Complexes trans-(C₆F₅)(p-tol₃P)₂Pt(C≡C)_nH (n = 2–4) and n-BuLi, Generation of Functional Equivalents of Pt(C≡C)_nLi Species, and Derivatization with Organic and Inorganic Electrophiles

Abstract

Reactions of the title complexes and n-BuLi (1.5 equiv, −45 °C) afford functional equivalents of the deprotonated species trans-(C 6 F 5 )(p-tol 3 P) 2 Pt(C�C) n Li (n = 2−4), as assayed by subsequent additions of MeI or Me 3 SiCl to give trans-(C 6 F 5 )(ptol 3 P) 2 Pt(C�C) n Me (66−52%) or trans-(C 6 F 5 )(p-tol 3 P) 2 Pt(C� C) n SiMe 3 (63−49%). However, 31 P NMR data suggest more complicated mechanistic scenarios, and small amounts of the hydride complex trans-(C 6 F 5 )(p-tol 3 P) 2 PtH (independently synthesized from the chloride complex, AgClO 4 , and NaBH 4 ) are detected in most cases. Analogous sequences involving trans-(C 6 F 5 )(ptol 3 P) 2 Pt(C�C) 2 H and benzyl bromide, D 2 O, or W(CO) 6 /Me 3 O + BF 4− similarly afford products with Pt(C�C) 2 Bn, Pt(C�C) 2 D, or Pt(C�C) 2 C(OCH 3 )�W(CO) 5 linkages. The crystal structures of the tungsten and corresponding SiMe 3 adduct, the three Pt(C� C) n Me species, and hydride complex are determined.