A pure composition comprises a monoalkyltin trialkoxide compound represented by the chemical formula RSn(OR′)3 or a monoalkyl tin triamide compound represented by the chemical formula RSn(NR′2)3 and no more than 4 mole % dialkyltin compounds relative to the total tin amount, where R is a hydrocarbyl group with 1-31 carbon atoms, and wherein R′ is a hydrocarbyl group with 1-10 carbon atoms. Methods are described for the formation of the pure compositions. A solid composition comprises a monoalkyl triamido tin compound represented by the chemical formula RSn—(NR′COR″)3, where R is a hydrocarbyl group with 1-31 carbon atoms, and where R′ and R″ are independently a hydrocarbyl group with 1-10 carbon atoms. The compositions are suitable for the formation of resist compositions suitable for EUV patterning in which the compositions have a high EUV absorption.