Decarboxylation of Stannyl Formates

If tripropyl- or tributyl-tin formate is heated at about 170 °C under reduced pressure, carbon dioxide is evolved and the corresponding tin hydride can be distilled off.28 The reaction is reversible, and in THF at 150 °C, the same equilibrium mixture is obtained from either side in ca. 40 h.29 

If a bis(trialkyltin) oxide (R3Sn)20 (R = Bu, Bu1, or Oct) is heated with one molar equivalent of formic acid, the formate decarboxylates to give the hydride, which reduces in situ the excess oxide to give the corresponding distannane (Section 18.2.1.3).30 

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