The purification of monoalkyl tin trialkoxides and monoalkyl tin triamides are described using fractional distillation and/or ultrafiltration. The purified compositions are useful as radiation sensitive patterning compositions or precursors thereof. The fractional distillation process has been found to be effective for the removal of metal impurities down to very low levels. The ultrafiltration processes have been found to be effective at removal of fine particulates. Commercially practical processing techniques are described.