Reaction #671029

Reaction equation

N-hydroxysuccinimide

N-t-butoxycarbonyl-methylalanine

1-(3-dimethylaminopropyl)-3-ethyl-carbodiimide

→

title compound

2-tert-Butoxycarbonylamino-2-methyl-propionic acid 2,5-dioxo-pyrrolidin-1-yl ester

Solvents

dichloromethane

Conditions

Workup

1. 1
   WashThe reaction mixture was washed three times each with saturated sodium bicarbonate solution
2. 2
   DryingThe organic layer was dried over sodium sulfate
3. 3
   Filtrationfiltered
4. 4
   Concentrationconcentrated in vacuo

Procedure

A stirred solution of N-hydroxysuccinimide (112 g, 0.973 mol), N-t-butoxycarbonyl-methylalanine (197 g, 0.969 mol), and 1-(3-dimethylaminopropyl)-3-ethyl-carbodiimide (186 g, 0.970 mol) in anhydrous dichloromethane (1.4 L) was stirred at room temperature for about 18 hours under nitrogen atmosphere. The reaction mixture was washed three times each with saturated sodium bicarbonate solution and then brine. The organic layer was dried over sodium sulfate, filtered and concentrated in vacuo to give the title compound of part 1-D as a white solid (256 g, 88%): PBMS (M+18)+ 318; 1H NMR=250 MHz (CDCl3) δ: 4.91 (NH, br s, 1H), 2.84 (—CO(CH2)2CO—, s, 4H), 1.67 (Me, s, 6H), 1.48 (BOC, s, 9H).

Source