Diethylethanolamine → (3R,4S)-3-amino-4-(3-boronopropyl)-1-(2-(diethylamino)ethyl)pyrrolidine-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A cooled (0° C.) solution of N,N-diethylethanolamine (82 mg, 0.70 mmol) and diisopropylethylamine (0.30 mL, 1.7 mmol) in anhydrous acetonitrile (12 mL) under nitrogen was treated with methanesulfonyl chloride (80.2 mg, 0.70 mmol), stirred 2.5 h, and treated with (3R,4S)-3-acetamido-N-tert-butyl-4-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)propyl)pyrrolidine-3-carboxamide (Example 8, step 4) (198 mg, 0.5 mmol) and heated to 60° C. for 15 h. The reaction mixture was concentrated, deprotected and isolated using the method described for example 8, step 5 to afford (3R,4S)-3-amino-4-(3-boronopropyl)-1-(2-(diethylamino)ethyl)pyrrolidine-3-carboxylic acid (120 mg, 57%) as a white foam. NMR (D2O) δ 3.97 (d, J=12.5 Hz, 1 H), 3.87 (m, 1 H), 3.65-3.80 (m, 3 H), 3.35-3.55 (m, 3 H), 3.19 (q, J=7.5 Hz, 4 H), 2.55-2.65 (m, 1 H), 1.50-1.65 (m, 1 H), 1.20 (t, J=7.5 Hz, 6 H), 1.15-1.35 (m, 3 H), 0.63-0.73 (m, 2 H). MS (m−H2O+1): 298.3; MS (m−2 H2O+1): 280.1.

Provenance & Evidence