Simultaneous displacement of a nitro group during coupling of diazotized o-nitroaniline with phenols

Abstract

During the diazo-coupling reaction, nucleophilic displacement of a nitro group was also observed. This was the main reaction (1→7) when the starting amine bore either a chlorine or methoxy group at the para position (1b-c). The newly prepared compounds (7) might serve as convenient building blocks in synthesis of some heterocycles. © Versita Sp. z o.o.

Synthesis of new potential UV-filters

“…1) and here we used its potential for the preparation of these starting materials [15,16]. Compound 1a was then treated with 2-(chloromethyl)prop-1-ene in the presence of KI and K 2 CO 3 to afford ether 2a, in good yield.…”

Construction of 2-(2′-Hydroxy-5′-methylphenyl)benzotriazole over Pd/γ-Al2O3 by a Continuous Process

“…Commercially available reagents were used without further purification. 2-Nitro-2′-hydroxy-5′-methylazobenzene (≥90%, determined by HPLC) was prepared by the customary procedures of diazotization and coupling …”

“…2-Nitro-2′-hydroxy-5′-methylazobenzene (≥90%, determined by HPLC) was prepared by the customary procedures of diazotization and coupling. 15 Preparation of Catalysts. The Pd/γ-Al 2 O 3 catalyst was prepared by incipient wetness impregnation, and the experimental details are described as follows: Initially, 50.00 g of pseudo-boehmite was kneaded vigorously with 60 mL water.…”

Rearrangement Reactions for the Synthesis of Some Oxa- and Aza-tricyclic Rings Heterocyclic Compounds

“…Compounds 52 were heated with methallyl chloride in the presence of K 2 CO 3 and KI to give ethers 53. Thermal rearrangement of the products in N,N-dimethylaniline afforded compounds 54, which were then silylated using heptamethyltrisiloxane and Karlstedt catalyst [Pt 2 (divinyltetramethyldisiloxane) 3 ] to give the desired products 55 in good yield [47][48][49].…”