Synthesis and bioactivity of 6‐bromo‐2‐(substituted)‐3‐(1‐phenyl‐ethyl)‐ 3,4‐dihydro‐1H‐ isophosphinoline 2‐chalcogenides

Abstract

Abstractmagnified imageSynthesis of 6‐bromo‐2‐(substituted)‐3‐(1‐phenyl‐ethyl)‐3,4‐dihydro‐1H‐isophosphinoline 2‐chalco‐genides derivatives (6) were synthesized from 2‐[(1‐phenylethylamino)methyl]‐4‐bromophenol (1) by reaction with aryl/alkyl phosphoro dichloridates (2) in the presence of triethylamine at 55°C to 60°C to obtained the title compounds (6a‐g). The title compounds (6h‐j), were prepared via intermediate route. Few other title compounds (8a‐c) were accomplished through a two step synthetic route involving 1 with dichlorophenyl phosphine (2a) and dichloroethyl phosphine (2a,b) in the presence of triethylamine in dry toluene under N2 atmosphere to form the corresponding trivalent phosphorus intermediate (7). In the second step they were further converted to the corresponding chalcogenides 8a‐c by reaction with hydrogen peroxide, sulfur and selenium respectively. They exhibited significant antibacterial, fungal and insecticidal activity.