• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.337-339
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• 2014

A facile one-pot synthesis of p-aminobenzoic acid from methyl 4-formylbenzoate which is a main by product in dimethyl terephthalate production process has been developed. This process involves the formation of amide intermediate obtained from the reaction of an aldehyde in methyl 4-formylbenzoate with chlorine in methylene chloride and the subsequent treatment of acid chloride with ammonia. The resulting amide was converted into amine using Hofmann degradation to afford a p-aminobenzoic acid. This facile one-pot process does not involve any expensive materials and should offer an attractive alternative to p-aminobenzoic acid production.

• Archives of Pharmacal Research
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• v.16 no.2
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• pp.158-160
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• 1993

2-Oxazolidinones and 1,3-oxazine-2-ones, key moieties of new antiulcer agents, were prepared successfully by treating corresponding hydroxyamide with N-bromosuccinimide (NBS) and silveracetate in acetonitrile. From the fact that the methods for the preparation of hydoxy amides are versatile and such amides could be converted to the corresponding 2-oxazolid-iones and 1,3-oxazine-2-one under our reaction condition, we think that our method is very practical one for the preparation of such compounds. In addition, the above synthetic example affords a good evidence of the synthetic applicability of our improved Hofmann rearrangement.

• Archives of Pharmacal Research
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• v.17 no.1
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• pp.39-41
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• 1994

Various N,N'-disubstituted ureas 5 were easily prepared from the corresponding primary amide 1 by tratment with N-Bromophthalimide $(NBP)-AgOAc-RNH$_{2}$ 4 in dry N,N-dimrthylformamide (DMF). This reaction envolved the intemediate formation of isocyanate 3 from amide 1 via Hofmann rearrangement by treatment with AgOAc and NBP and nucleophilic addition of amine 4 to this isocyante 3. This method is simple enough to be applied to the synthesis of various N,N'-disubstututed ureas scale conviently.

• YAKHAK HOEJI
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• v.36 no.3
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• pp.250-254
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• 1992

Benzo[C]phenanthidine alkaloids were found to exhibit considerably strong antileukemic activies. These alkaloids have been shown to be biosynthesized from the corresponding alkaloids throung an oxidative $C_6-N$ bond cleavage followed by recyclization between $C_6\;and\;C_{13}$ position of the protoberberine. Recently we have achieved the biomimetic transformation of protoberberine alkaloid, berberine into benzo[C]phenanthridine alkaloid, chelerythrine.

• Textile Coloration and Finishing
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• v.5 no.4
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• pp.20-28
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• 1993

Primary amino group was introduced into cellulose by the Hofmann reaction from carbamoylethylated cotton fabrics. Cabamoylethylated cotton was prepared by treating the cotton fabrics with acrylamide and sodium hydroxide catalysts. These amino group altered physical and chemical properties of cotton fabrics. The influence of reactive dyeing, tensile strength and crease recovery was investigated. The exhaustion of reactive dye with cationized cotton fabrics was increase with acrylamide concentration. The pH value of maximum exhaustion was exchanged from 11.0 to 9.0 in cationized cotton fabrics.