Ammonia → (2R,4R)-1-tert-butyl 2-methyl 4-(3-(4-cyanophenyl)ureido)piperidine-1,2-dicarboxylate

4-isocyanatobenzonitrile (1.17 g, 8.13 mmol) was added to a solution of (2R,4R)-1-tert-butyl 2-methyl 4-aminopiperidine-1,2-dicarboxylate (2.0 g, 7.7 mmol) and NEt3 (1.3 mL, 9.3 mmol) in THF (30 mL), and the resulting solution was stirred at room temperature for 6 hours. 1M ammonia in methanol (5 mL) was added to reaction mixture to quench excess isocyanine. Water (100 mL) and ethyl acetate (200 mL) were added to the mixture. The organic layer was separated and dried over MgSO4 and concentrated to give a solid. Purification was done by Companion (ReadySep, 80 g, silica gel packed) with ethyl acetate/heptane from 40-70% to give the urea as a white solid 2.9 g (90%). LC-MS: 403.2, 401.3 (t=2.6 min).

1. customto quench excess isocyanine
2. additionWater (100 mL) and ethyl acetate (200 mL) were added to the mixture
3. customThe organic layer was separated
4. dry with materialdried over MgSO4
5. concentrationconcentrated
6. customto give a solid
7. customPurification

ORD record

ord-402aa2c149f249c2bd27555ee17c9c81

Source dataset

uspto-grants-2012_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08148401B2