• YAKHAK HOEJI
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• v.33 no.5
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• pp.290-295
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• 1989

2,6-Dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid methyl ester (1) was formylated to 2,6-dimethy-4-(3'-nitrophenyl)-5-formyl-1,4-dihydropyridine-3-carboxylic acid methyl ester (2) in 76% yield. At the elevated temperature, 2,6-dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-monomethyl ester (3) was also converted into compound 2 in 46% yield. The compound 2 was reduced to 2,6-dimethyl-4-(3'-nitrophenyl)-5-hydroxymethyl-1,4-dihydropyridine-3-carboxylic acid methyl ester (4) in 91% yield. Compound 2 was reacted with triethyl phosphonoacetate to give 2,6-dimethyl-4-(3'-nitrophenyl)-5-(2-ethoxycarbonyl ethenyl)-1,4-dihydropyridine-3-carboxylic acid methyl ester (5) in 50% yield. Reaction between compound 2 and amines (methyl amine, ethylamine, methoxylamine, hydroxyl amine, phenyl hydrazine and 1-amino-4-methyl piperazine) gave six schiff bases 7a, 7b, 7c, 7e, 7f in 81%, 91%, 82%, 81%, 50% and 84% yield, respectively.

• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.335-338
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• 2009

As important intermediates for blue emitting materials of organic light-emitting diodes, bromotriphenylethylene derivatives for distrylarylenes are prepared by reactions of bromobenzophenone with benzylphosphonates. The reaction produces a 60 : 40 mixture of (Z)- and (E)-geometric isomers that are difficult to be resolved. The (Z)-isomer is successfully isolated by a selective recrystallization process using 2-propanol as a solvent. The X-ray structure analysis of (Z)-isomer shows that dihedral angles between tert-butylphenyl ring and bromophenyl ring and between bromophenyl ring and phenyl ring are $56.5(4)^{\circ}$ and $74.1(4)^{\circ}$, respectively.