Lewis acid promoted direct synthesis of tetraalkynylstannanes

Oxidative coupling of tetraalkynyltin with aldehydes leading to alkynyl ketones

“…The starting tetraalkynyltin 1a-d were obtained according to the reported methods. 25,27 Aldehydes 2a-h, k, m-o are commercially available (Aldrich). Aldehyde 2l was prepared according to the known procedure.…”

“…Recently, we have developed two convenient methods for the preparation of tetraalkynyltin compounds (RCRC) 4 Sn, by a reaction of 1-alkynes either with SnCl 4 in the presence of anhydrous ZnCl 2 and Et 2 NH, 25,26 or with tin tetra(N,N-diethylcarbamate) in the presence of anhydrous ZnCl 2 . 27 It is noteworthy that although tetraalkynyltin compounds were first prepared as early as the 1950s, 28 their synthetic potential was not sufficiently realized.…”

Tetraalkynylstannanes in Synthesis of α,β-Acetylenic Ketones

“…Recently, we reported the Stille-type coupling reaction of tetraalkynylstannanes with aryl halides leading to aryl acetylenes and SnHal4 [12] and aldehydes leading to alkynyl ketones [13,14]. Earlier, we developed convenient methods for preparation of tetraalkinyltin species from either SnCl4 [15] or tin tetra(N,N-diethylcarbamate) [16].…”

Tetraalkynylstannanes in the Stille cross coupling reaction: a new effective approach to arylalkynes

“…The alkynyl fragment can be easily introduced onto a tin atom in different ways. Recently we have developed two convenient and effective methods of synthesis of tetraalkynylstannanes 1 (Scheme 2); the first is based on the direct reaction of terminal alkynes with SnCl 4 in the presence of anhydrous ZnCl 2 and diethylamine 20,21 and the next is based on the reaction of tin tetra(N,N-diethylcarbamate) with phenylacetylene. 22 Tetraalkynylstannanes 1 are oily or solid compounds that can be easily purified and isolated in good yields after column chromatography on a silanized silica.…”