Dimethyl oxalate → HCID 13729868, compound

HRID 1034360Notes

Reaction equation

[C:1]1([CH:7]=[CH:8][C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][C:10]=2Br)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[Mg].[C:17](OC)(=[O:22])[C:18]([O:20][CH3:21])=[O:19]>C1COCC1>[C:1]1(/[CH:7]=[CH:8]\[C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][C:10]=2[C:17](=[O:22])[C:18]([O:20][CH3:21])=[O:19])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1

Participants

Conditions

Temperature: -15 °C

Procedure

A solution of the Grignard agent prepared from part of the mixture of isomers of 1-phenyl-2-(2-bromophenyl)ethylene described above (5.58 g) and magnesium (0.63 g) in dry THF (20 ml) was added dropwise over 30 mins. to a stirred solution of dimethyl oxalate (5.06 g) in dry THF (40 ml) cooled to -15° C. The resulting mixture was stirred at about -15° C. for 30 minutes, then at room temperature for 1 hour, then poured into dilute hydrochlorice acid and extracted with ether. The extracts were washed with water, dried, concentrated under reduced pressure, then chromatographed twice [(i) 30% ether in petrol; (ii) 20% hexane in dichloromethane] to give isomerically pure Z-methyl 2-(2'-phenylethenyl)phenylglyoxalate (1.76 g, 31% yield) as a yellow oil, 1H nmr (CDCl3): delta 3.87 (3H, s), 6.78 centre of 2 doublets, each 1 H, J 12 Hz) p.p.m.

Workup

additionwas added dropwise over 30 mins
waitat room temperature for 1 hour
additionpoured
additioninto dilute hydrochlorice acid
extractionextracted with ether
washThe extracts were washed with water
customdried
concentrationconcentrated under reduced pressure
customchromatographed twice [(i) 30% ether in petrol; (ii) 20% hexane in dichloromethane]

Sources & evidence

ORD record: ord-881bec2e6ae84b1487f9320968577062
Source dataset: uspto-grants-1994_05
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05315025

Reaction notes

Loading…