Diels–Alder reactions of organotin maleates

The ability of organotin maleates to undergo Diels–Alder reactions with a range of dienes has been examined. Crystalline adducts have been obtained from 2,3-dimethylbuta-1,3-diene with triphenyltin methyl maleate and from cyclopentadiene with triphenyltin methyl maleate, tributyltin methyl maleate, dibutyltin bis(methyl maleate), and dibutyltin maleate. The products expected from the Diels–Alder reactions of 2,3-dimethylbuta-1,3-diene with triphenyltin methyl maleate, tributyltin methyl maleate and dibutyltin bis(methyl maleate) have been synthesised by an alternative method.