1-bromo-2-(2-phenylethenyl)benzene

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:-15.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of the Grignard reagent 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 hydrochloric 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 (3 H, s), 6.78 (centre of 2 doublets, each 1 H, J 12 Hz) p.p.m. was added dropwise over 30 mins at room temperature for 1 hour extracted with ether The extracts were washed with water dried concentrated under reduced pressure chromatographed twice [(i) 30% ether in petrol; (ii) 20% hexane in dichloromethane]

Conditions: temp:-15.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

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. was added dropwise over 30 mins at room temperature for 1 hour poured into dilute hydrochlorice acid extracted with ether The extracts were washed with water dried concentrated under reduced pressure chromatographed twice [(i) 30% ether in petrol; (ii) 20% hexane in dichloromethane]

Conditions: temp:-15.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of the Grignard reagent 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 hydrochloric 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 (3 H, s), 6.78 (centre of 2 doublets, each 1 H, J 12 Hz) p.p.m. was added dropwise over 30 mins at room temperature for 1 hour extracted with ether The extracts were washed with water dried concentrated under reduced pressure chromatographed twice [(i) 30% ether in petrol; (ii) 20% hexane in dichloromethane]

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:-15.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of the Grignard reagent 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 hydrochloric 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 12Hz) p.p.m. was added dropwise over 30 mins at room temperature for 1 hour extracted with ether The extracts were washed with water dried concentrated under reduced pressure chromatographed twice [(i) 30% ether in petrol; (ii) 20% hexane in dichloromethane]

Conditions: temp:-15.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

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. was added dropwise over 30 mins at room temperature for 1 hour poured into dilute hydrochlorice acid extracted with ether The extracts were washed with water dried concentrated under reduced pressure chromatographed twice [(i) 30% ether in petrol; (ii) 20% hexane in dichloromethane]

Conditions: temp:-15.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of the Grignard reagent 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 hydrochloric 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 (3 H, s), 6.78 (centre of 2 doublets, each 1 H, J 12 Hz) p.p.m. was added dropwise over 30 mins at room temperature for 1 hour extracted with ether The extracts were washed with water dried concentrated under reduced pressure chromatographed twice [(i) 30% ether in petrol; (ii) 20% hexane in dichloromethane]