To a 500 mL round bottom flask equipped with stir bar and N₂ inlet adaptor was added 12.13 g (0.08542 mol, 1 equiv) of 3-trimethylsilylcyclobutanone was added to a along with 250 mL of a 95:5 2-propanol : water  solution(0.353 M in the cyclobutanone). KBH₄ (7.01g, 0.1281 mol, 1.5 molar equiv) was added to the flask via a ground glass funnel^a,b,c and the solution reaction mixture was placed under a N₂ atmosphere. Reaction progress was monitored by GC-MS and, after about 1.5 hr, the reaction was complete.

2-Propanol was removed via rotary evaporation until a cloudy slurry remained. The slurry was diluted with diethyl ether (≈ 200 mL) and was transferred to a 1000 mL separatory funnel. The organic layer was washed with aqueous NaOH (100 mL, 1 M) to remove the boric acid byproduct. The two layers were separated and the aqueous layer was then re-extracted with ether (3X 100 mL). The organic layers were combined and washed with 150 mL brine. The organic layer was dried with Na₂SO₄ and the volatiles were removed via rotary evaporation under aspirator vacuum in a heated water bath (70^oC).  A cloudy oil remained and was further purified by vacuum distillation (bp 80 ^oC at 30 mm Hg) giving 3-trimethylsilylcyclobutanol as a colorless oil (9.13g,  74.2%).   Ratio of the cis to trans  isomers was determined to be 93:7 by both NMR and GC-MS.²  

Data is for the major cis isomer  unless otherwise indicated:

¹H-NMR (CDCl₃, 300 MHz) δ -0.03 (9H, s),  0.93-1.06 (1H, m), 1.59-1.71 (2H, m), 2.10 (1H, d, OH, J = 7.0 Hz), 2.21-2.32 (2H, m);  trans δ -0.05 (9H, s, Me₃Si) – other peaks for the trans isomer were too small to be seen or were obscured by the other isomer

 ¹³C NMR (CDCl₃ 75 MHz) δ -3.35 (CH₃), 11.59 (CH), 35.00 (CH₂), 67.11 (CH). trans δ -3.20 (CH₃), 11.21 (CH), 34.16 (CH₂), 66.90 (CH)

GC-MS (EI) 144 ([M]⁺, 0.33%), 143 ([M-H]⁺, 0.59%), 129 ([M-CH₃]⁺, 32.9%) 116 (4.3%), 101 (7.8%), 85 (18.1%), 75 (78.4 %), 73 (100%), 59(15.0%), 54 (24.0%), 45 (24.0%) 43 (20.7%).