Reaction #1973911

Reaction equation

9-(2-Benzyloxy-ethyl)-8-chloro-5-methoxy-2,3,4,9,-tetrahydro-1H-carbazole-4-carboxylic acid

oxalyl chloride

→

9-(2-Benzyloxy-ethyl)-8-chloro-5-methoxy-2,3,4,9,-tetrahydro-1H-carbazole-4-carbonyl chloride

Solvents

dichloromethane

Conditions

Workup

1. 1
   Otherfor about 30 min
2. 2
   ConcentrationThe reaction was then concentrated in vacuo

Procedure

9-(2-Benzyloxy-ethyl)-8-chloro-5-methoxy-2,3,4,9,-tetrahydro-1H-carbazole-4-carboxylic acid (7) (1.5 g, 3.7 mmol) was dissolved in dichloromethane (50 mL) and oxalyl chloride (700 mg, 5.5 mmol, 470 μL) and DMF (1 drop) were added and the reaction stirred at 20° C. for 2 h. There was a moderate evolution of gas for about 30 min as the reaction proceeded. The reaction was then concentrated in vacuo to give 9-(2-Benzyloxy-ethyl)-8-chloro-5-methoxy-2,3,4,9,-tetrahydro-1H-carbazole-4-carbonyl chloride (8) as a gum which was used into the next step without purification. The structure was confirmed by 13C NMR (75 MHz; CDCl3): δC 20.8, 22.1, 26.4, 44.2, 51.8, 55.1, 70.7, 73.3, 100.7, 106.0, 108.6, 119.5, 123.4, 127.3, 127.7, 128.3, 131.9, 138.0, 138.2, 152.0. and 176.3.

Source