2.6- Dibromo-4-aminophenol

Dibromoquinone-4-chloroimide has been prepared by the action of sodium hypochlorite on 2,6-dibromo-4-aminophenol in the form of the chlorostannate1 or as the hydrochloride.2... 

To a solution of 3.0 g 2,6-dibromo-4-aminophenol hydrochloride (10 mmol) in dry warm ethanol was added a cone, ethanol solution of 2.9 g 4-[A,A-bis(2-chloroethyl)amino]-3-ethoxybenzaldehyde (10 mmol). The resulting dark red solution was stirred for a few hours and then cooled in ice to deposit the crystal solid. The crystal was filtered and washed with absolute ethanol and diethyl ether, and dried to afford 3.4 g 4-( 4-[A,A-bis(2-chloroethyl)amino]-3-ethoxybenzylidene -amino)-2,6-dibromophenol hydrochloride, in a yield of 70%. 

HC—C( NC1)—CH mw 210-46 yel ndls (from ale), mp 67-68° was prepd from the HCl salt of 2,6-dichlofo-4 aminophenol by treating it with an acidic chloride of lime soln (Ref 1) It is reported by B.T. Taranto of Schering Cotp, Bloomfield, NJ (Ref 2) that this reagent, used for spot visualization in chromatographic systems, presents a potential expln hazard. Tests of this compd and of the 2,6-Dihromo deriv (qv) in a thermal stability bomb showed both to be expl, but the dichloro deriv was not as unstable as the dibromo deriv Refs 1) Beil 7, 634 2) Anon, C EN 45,... 

The catalyzed hydrocyanation of imines (Strecker reaction) has the option of employing a stable (salen)aluminum chloride or a Zr complex of 6,6 -dibromo-BINOL, with BujSnCN. It is important to derive the imines firom o-aminophenol for the present purpose. 

Dimedone was treated with two equivalents of bromine in glacial acetic acid to yield 2,2-dibromo-5,5-dimethylcyclohexane-l,3-dione. The dibromo compound was subjected to reaction with substituted 2-aminothiophenols, 2-aminophenol, thiocarbohydrazones, and triazoles to furnish spiro-(2, 6 -dioxo-4, 4 -dimethylcyclohexane)-6-substituted-l,... 

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