Amido-derivatives of metals and metalloids. Part IX. Reactions of tin(IV) and titanium(IV) amides with compounds having carbonyl and sulphinyl multiple bonds

Abstract

Titanium(IV) and tin(IV) amides (reactivity: Ti > Sn) are useful reagents for some organic aminations. Reactions of R₃Sn·NMe₂(R = Me or Buⁿ) or Ti(NMe₂)₄ with some carboxylic acids, anhydrides, amides, esters (alkyl, phenyl, enol, β-oxo, and αβ-unsaturated), and aldehyde, and acetone are reported. The following types were found: (i)(for most esters, CH₂:1;CH·CO₂H, and Ac₂O), metathetical exchange with acyl–oxygen cleavage affording carboxylic acid amides; (ii)(for Me₃Sn·NMe₂ with CH₂:1;CH·OAc), metathetical exchange with alkyl–oxygen fission; and (iii)(for Buⁿ₃Sn·NMe₂ with AcOH), protonolysis. Amination of sulphur dioxide with Ti(NMe₂)₄ afforded SO(NMe₂)₂, while methyl sulphoxides (MeSOR; R = Me or C₆H₁₁) were reductively aminated by the same reagent to afford Me₂N·CH₂SR.