Disproportionation of Sn(ii){CH(SiMe₃)₂}₂ to ˙Sn(iii){CH(SiMe₃)₂}₃ and ˙Sn(i){CH(SiMe₃)₂}: characterization of the Sn(i) product

Abstract

Half a century since the photocatalytic disproportionation of Lappert's dialkyl stannylene SnR2, R = CH(SiMe3)2 (1) gave the persistent trivalent radical [·SnR3], the characterization of the corresponding Sn(I) product, ·SnR...

Sn(ii)–carbon bond reactivity: radical generation and consumption via reactions of a stannylene with alkynes

“…2.0–2.5 eV) 8,9 and often well-defined Sn( i ) radical character. 10,11 It has been shown that stannylenes react with H 2 , 9,12,13 CO 2 , 14–16 RNH 2 , 9 and ROH (R = Me or H) 17 and ethylene 6 under mild conditions.…”

“…6,23,30 Homolytic cleavage of a Sn–C bond was initiated upon heating, followed by the formation of a :ṠnAr iPr4 radical and a terphenyl carbon radical ˙Ar iPr4 , which can be contrasted with the generation of the radical ˙Sn{CH(SiMe 3 ) 2 } 3 by heating hydrocarbon solutions of {Sn{CH(SiMe 3 ) 2 } 2 } 2 . 10,11,39 The reaction of the :ṠnAr iPr4 /˙Ar iPr4 radical pair with phenylacetylene yielded the product 1 . In the synthesis of 2 , the ˙Ar iPr4 is not added to the alkyne substrate, likely for steric reasons.…”