In a flame-dried three-neck flask, a solution of 2-(benzyloxymethyl)-2H-tetrazole (2.01 g, 10.57 mmol) and tetramethylethylenediamine (3.16 mL, 21.4 mmol) in diethyl ether (30 mL) was cooled to −78° C. Once at the prescribed temperature, the mixture was treated with the dropwise addition of n-butyllithium (1.6 M in hexanes, 7.3 mL, 11.62 mmol), which caused the color of the solution to turn dark red. Upon completion of addition, the mixture was stirred for 10 minutes, and then transferred via cannula to a solution of tributyltin chloride (2.9 mL, 10.57 mmol) in diethyl ether (20 mL) which had been pre-cooled to −78° C. Upon completion of the transfer, the reaction was stirred for 45 minutes, and then quenched with saturated ammonium chloride solution. The mixture was allowed to come to room temperature, and the aqueous and organic layers were separated. The aqueous phase was extracted 3× with ethyl acetate, and the combined organic phases were washed with brine, dried over sodium sulfate, and concentrated in vacuo to yield a residue. The residue was purified over silica gel, eluting with 1% then 5% then 10% ethyl acetate/hexanes to yield 2-(benzyloxymethyl)-5-(tributylstannyl)-2H-tetrazole (3.0 g, 60% yield) as a colorless oil.
