Amino phenyl propiolic acid

The following are examples of the reduction of nitro-compounds by ferrous sulphate nitro-phenyl propiolic acid1 and nitro-dichlor-benzaldeliyde2 the method has been used to reduce several nitro-acids to the corresponding amino-acids.3... 

OxazoIones are alkylated at position 4 by alkyl halides, allyl halides and electrophilic alkynes, such as methyl propiolate (equation 36). In contrast, 2-phenyloxazolones react with methyl vinyl ketone at both C(4) and C(2) to yield a mixture of Michael adducts (equation 37). If the phenyl substituent is replaced by the bulky 2,4,6-trimethylphenyl group the addition is directed exclusively to C(4) (81CB2580). Alkylation of 5(4//)-oxazolones is a key step in the synthesis of ketones from a-amino acids (Scheme 16). The outcome of this sequence is the union of the electrophilic fragment R3 with the group R2CO the amino acid thus functions as the equivalent of an acyl anion (78AG(E)450). 

Dienoic acid derivatives such as 1.281 can be prepared by modification of other amino acids. The condensation of ethyl 3-(N-benzylamino)but-2-enoate 1.280) and ethyl propiolate gave ethyl 5-(N-benzylamino)-4-carboethoxyhexa-2Z.4E-dienoate. 1.281. Changing the 3-methyl group in the alkenyl amino acid to phenyl or hydrogen allowed the synthesis of other dienoic acid derivatives. In this study, the N-alkyl group was also modified from benzyl to hydrogen or methyLf ... 

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