New type of reactions of stannylenes with organic azides: Theoretical study

Density functional study of the reaction of Sn(OCH2CH2NMe2)2 (1) with Me3Si-N3 (2) yielding the redistribution product [(N3)SnOCH2CH2NMe2]2 (3) has been performed at the PBE/TZ2P(SBKJC) level. Two possible reaction paths, the formation of [(N3)SnOCH2CH2NMe2]2 (path A) and initially expected imine Me3Si-NSn(OCH2CH2NMe2)2 (5) (path B), have been studied. The formation of the imine 5 is thermally more favorable than the formation of dimeric stannylene 3, ΔG0(5) = −6.7 kcal/mol and ΔG0(3) = −5.9 kcal/mol. The reaction proceeds to 3 due to a lower energy barrier, ΔG‡ = 27.8 and 39.5 kcal/mol for 3 and 5, respectively.