Heteroleptic tin (II) dialkoxides stabilized by intramolecular coordination Sn(OCH2CH2NMe2)(OR) (R = Me, Et, iPr, tBu, Ph). Synthesis, structure and catalytic activity in polyurethane synthesis

A straightforward method of synthesis of heteroleptic tin (II) alkoxides stabilized by one intramolecular coordination bond was developed. Addition of one equivalent of dimethylamino ethanol to diamide Sn(N(SiMe3)2)2 (5) yields alkoxy-amido derivative Sn(OCH2CH2NMe2)(N(SiMe3)2) (2). Further addition of alcohol leads to corresponding heteroleptic dialkoxides Sn(OCH2CH2NMe2)(OR) (R = Me (6), Et (7), iPr (8), tBu (9), Ph (10)). Catalytic activity of tin (II) compounds in polyurethane formation was tested.