Two quasi-stable lead(ii) hydrides at ambient temperature

Abstract

Simple reactions of their terphenyl lead bromide precursors with DIBAL-H in diethyl ether solution at ca. −78 °C leads to the isolation of the hydrides {Pb(μ-H)Ar^Pri₄}₂ (Ar^Pri₄ = C₆H₃-2,6-(C₆H₃-2,6-Prⁱ₂)₂) (1) and {Pb(μ-H)Ar^Me₆}₂ (Ar^Me₆ = C₆H₃-2,6-(C₆H₂-2,4,6-Me₃)₂) (2) in good yield (60–80%). The isolated solids are stable at up to 5 °C for several weeks but are thermally labile in solution. Hydride 1 decomposes to the diplumbyne Ar^Pri₄PbPbAr^Pri₄, while 2 decomposes to the plumbylene Pb(Ar^Me₆)₂. The decomposition of 1 was determined to be zero order with a rate constant of ca. 2.0 × 10⁻⁵ M min⁻¹ at 298 K.