Réaction #1772063

Équation de réaction

3-Nitrostyrene

2,3:4,6-di-O-isopropylidene-2-keto-L-gulonic acid monohydrate

urea hydrogen peroxide

→

(3-Nitrophenyl)oxirane

Rendement 75.0%

Solvants

dichloromethane

Conditions de réaction

Traitement

1. 1
   FiltrationThe mixture was filtered
2. 2
   Lavagewashed the residue with dichloromethane
3. 3
   Autrevacuum flash evaporator
4. 4
   AutreThe product was purified by preparative TLC with 25% EtOAc/hexane

Mode opératoire

3-Nitrostyrene (1 g, 6.71 mmol) was taken with 100 mg Immobilized lipase and 2,3:4,6-di-O-isopropylidene-2-keto-L-gulonic acid monohydrate (0.3 g, 1.03 mmol) in dry dichloromethane (15 mL) and stirred at 25° C. and added urea hydrogen peroxide (3 g, 32 mmol) portion-wise at a pH 5 for 20 hours. The reaction was monitored occasionally on TLC. The mixture was filtered and washed the residue with dichloromethane and the filtrate was reduced its volume under reduced pressure using vacuum flash evaporator. The product was purified by preparative TLC with 25% EtOAc/hexane. 75% Yield; Yellow oil (Found: C, 58.22; H, 4.28; N, 8.50. C8H7NO3 requires C, 58.18; H, 4.27; N, 8.48%); Rf (25% EtOAc/hexane) 0.50; [α]D20−1.51 (c 2.0, CHCl3); {lit., [α]D18+2.5 (c 2.8, CHCl3, S}; HPLC analysis using a Chiralpak AD column showed it to be 60% ee [hexane: 2-propanol=9:1, flow rate 0.8 cm3 min−1]; νmax (neat/cm−1) 3113, 2995, 1517, 1343, 1301, 1042, 983, 888, 788, 740; δH (300 MHz; CDCl3) 2.80 (1H, dd, J 2.5 and 4.8, HCOCHH), 3.21 (1H, dd, J 3.9 and 4.8, HCOCHH), 3.97 (1H, dd, J 2.5 and 3.9, PhCHOCH2), 7.40-7.75 (2H, m, 2×CH, arom.) and 8.01-8.24 (2H, m, 2×CH, arom.); δC (300 MHz; CDCl3) 51.7 (CH2), 51.9 (CH), 126.0, 126.4, 145.4 and 148.6 (6×C-Ph); MS m/z (rel. intensity %): 165 (M+, 18), 150(32), 136(68), 120(25), 105(17), 90(100), 77(22), 74(12), 65(52), 63 (59).

Source