Water → HCID 178506641, compound

Participants

Reaction Conditions

Reaction Steps

A dry 100 mL round-bottomed flask equipped with a mechanical stirrer, a reflux condenser, a low temperature thermometer and a silicone rubber septum was flushed with argon. 2-benzo[B]thienyllithium was prepared in situ from 1.1 g of benzo[B]thiophene (8.21 mmol) and 3.3 mL of 2.5 m solution of n-BuLi (in hexanes) in 20 mL of ether. The mixture was cooled to -90° C. and the solution of dichlorocyclopentylborane obtained in step 1 was added over 10 min while stirring was maintained. The mixture was brought to 20° C. and stirred for 2 h at this temperature. Distilled water (20 mL) was added with vigorous stirring. The top layer formed was separated and discarded. The aqueous layer was poured into 30 mL of saturated solution of NME4CL and shaken. The precipitate formed was filtered, washed with 60 ml of distilled water, and recrystallized from acetone/methanol=3/2 yielding 1.2 g (79%) of white crystalline solid. m.p. 234-236° C. 1H NMR (D6 -DMSO, 200 MHz) δ 7.69 (d, J=7.6 Hz, 3H), 7.57 (d, J=7.6 Hz, 3H), 7.14 (t, J=7.4 Hz, 3H), 7.07 (s, 3H), 7.04 (t, J=7.4 Hz, 3H), 3.04 (s, 12H), 1.85 (m, 2H), 1.65 (m, 1H), 1.37 (br s, 6H). 13C NMR (D6 -DMSO, 50 MHz) δ 141.9, 124.1, 122.5, 121.4, 120.9, 54.51 (t, J=4 HZ), 31.38, 27.34. 11B NMR (DMSO, 128 MHz) δ -30.36. Anal. Calcd. for C33H36BNS3 : C, 71.59; H, 6.55; N, 2.53; S, 17.37. Found: C, 71.50; H, 6.63; N, 2.53; S, 17.30.

Provenance & Evidence