HCID 10160091, compound → HCID 87858589, compound

Participants

Reaction Steps

Irradiation of 0.2% solutions of α-(3-methoxyphenyl)-4,5-dimethoxy-2-nitrobenzyltrichloroacetate (38) and α-phenyl-4,5-dimethoxy-2-nitrobenzyltrichloroacetate (39) in acetonitrile resulted in nearly quantitative conversions into the expected photoproducts, 4,5-dimethoxy-3′-methoxy-2-nitrosobenzophenone (50) and 4,5-dimethoxy-2-nitrosobenzophenone (51), respectively, after less than 4 minutes. Irradiations at lower concentrations, monitored by UV, resulted in even faster photoreactions. When a 0.004% solution of α-phenyl-4,5-dimethoxy-2-nitrobenzyltrichloroacetate (39) was irradiated, there was a quantitative conversion into the photoproduct after 30 seconds. The two esters appeared to have a similar rate of photoconversion but the photolysis of α-phenyl-4,5-dimethoxy-2-nitrobenzyltrichloroacetate (39), quantum yield φ˜0.14, was cleaner with less amount of polar secondary photoproducts. These properties, coupled with the reduced inner filter effect and absorption maximum at 345 nm, make compound 39 a prime candidate for use in the microarray format.

Provenance & Evidence