Reaction #83394

Reaction equation

L-Pyroglutamic acid methyl ester

NaH

p-Cyanobenzylbromide

→

N-(4-Cyanobenzyl)-L-pyroglutamic acid methyl ester

Solvents

THF

Conditions

Workup

1. 1
   workup.ADDITIONwas added
2. 2
   workup.WAITthe mixture left
3. 3
   OtherAfter 48 h the reaction mixture was partitioned between EtOAc and satd NaHCO3 solution
4. 4
   Otherthe aqueous layer separated
5. 5
   Washwashed with CH2Cl2
6. 6
   Washwashed with brine
7. 7
   Dryingdried (MgSO4)
8. 8
   FiltrationFiltration and concentration to dryness
9. 9
   Othergave the white solid product

Procedure

L-Pyroglutamic acid methyl ester (1.36 g, 0.0095 mol) was dissolved in dry THF (20 mL) under Ar, treated with NaH (60% oil dispersion) (0.58 g, 0.0145 mol) with stirring for 5 min, then the mixture was cooled to 0° C. p-Cyanobenzylbromide (1.78 g, 0.0091 mol) was added, and the mixture left to slowly warm to ambient temperature. After 48 h the reaction mixture was partitioned between EtOAc and satd NaHCO3 solution, the aqueous layer separated and washed with CH2Cl2, the organics combined, washed with brine and dried (MgSO4). Filtration and concentration to dryness followed by trituration with ether gave the white solid product. 1H NMR(CDCl3, 400 MHz) δ 7.62(2H, d, J=8 Hz), 7.33(2H, d, J=8 Hz), 4.98(1H, d, J=15.4 Hz), 4.13(1H, d, J=15.4 Hz), 3.99(1H, dd, J=3, 9 Hz) and 2.5-2.6 (1H, m), 2.4-2.5 (1H, m), 2.2-2.45 (1H, m), 2.1-2.2 (1H, m) ppm.

Source