Carbon Dioxide → HCID 71264970, compound

Participants

Reaction Steps

To a solution of R-5 (47 mmol, 9.5 g) in THF (2000 mL) at −78° C. is added n-BuLi (1.6M in hexanes, 104 mmol, 65 mL). The mixture is stirred for 15 min before the dry ice bath is removed. After 5 min dry ice is added. Water is added and the pH adjusted to 3 with 1N HCl. The mixture is saturated with NaCl and extracted with ethyl acetate (3×20 mL). Organics are combined and dried over MgSO4 and concentrated in vacuo. The crude is purified by flash chromatography to give R-6 (7.6 g, 97%). R-6 (7.2 mmol, 1.2 g) is dissolved in DMF (30 mL) followed by piperidine (36 mmol, 3.00 g) then HATU (2-(7-Aza-1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate) (8.7 mmol, 3.3 g). The mixture is stirred at ambient temperature for 3 h. Water is added and the mixture extracted with ethyl acetate. Organics are combined, washed with brine, dried over MgSO4 and concentrated in vacuo. The residue is purified by HPLC to yield the title intermediate (1.10 g, 65%).

Provenance & Evidence