Methyl stannic chloride, SnCH₃Cl₃

Methyl stannic chloride, SnCH₃Cl₃, prisms melting at 53° C.; methyl stannic bromide, SnCH₃Br₃, needles melting at 53° C.; methyl stannic iodide, SnCH₃I₃, yellow prisms melting at 86.5° C., are formed by the action of the corresponding halogen hydracid on methyl stannic acid, SnCH₃-O-OH, and are converted into the latter substance by the action of ammonia. Methyl stannic acid, which may be regarded as methyl stannonic acid, CH₃-SnO-OH, is obtained by the action of methyl iodide on potassium stannite, thus:

HSnO-OK + CH₃I + KOH = CH₃SnO-OK + KI + H₂O,

the resulting potassium salt being then decomposed by carbonic acid. When warmed with alkali solution, however, the potassium salt gradually produces dimethyl stannone and potassium stannate, thus:

2CH₃SnOOK = (CH₃)₂SnO + SnO(OK)₂,

by a change analogous to that which acetate undergoes when heated:

2CH₃COOK = (CH₃)₂CO + CO(OK)₂;

and when dimethyl stannone is distilled with alkali it yields trimethyl stannic hydroxide, (CH₃)₃-Sn-OH, thus:

3(CH₃)₂SnO + 2KOH = 2(CH₃)₃SnOH + SnO(OK)₂.