Benzene-1,3-dicarboxyhc acid

When a dilute solution of 6 phenylhexanoyl chloride in carbon disulfide was slowly added (over a period of eight days ) to a suspension of aluminum chloride in the same solvent it yielded a product A (C12H14O) in 67% yield Oxidation of A gave benzene 1 2 dicarboxyhc acid... 

Friedel-Crafts Acylation. The Friedel-Crafts acylation procedure is the most important method for preparing aromatic ketones and thein derivatives. Acetyl chloride (acetic anhydride) reacts with benzene ia the presence of aluminum chloride or acid catalysts to produce acetophenone [98-86-2], CgHgO (1-phenylethanone). Benzene can also be condensed with dicarboxyHc acid anhydrides to yield benzoyl derivatives of carboxyHc acids. These benzoyl derivatives are often used for constmcting polycycHc molecules (Haworth reaction). For example, benzene reacts with succinic anhydride ia the presence of aluminum chloride to produce P-benzoylpropionic acid [2051-95-8] which is converted iato a-tetralone [529-34-0] (30). 

Methyl-1 -phenylethyl)-4-(2-propynyloxy)benzene, 3754 3-Methyl-2-penten-4-yn-l-ol, 2378 2-Methyl-3,5,7-octatriyn-2-ol, 3129 f 2-Methyl-3-butyn-2-ol, 1904 2-Nitrophenylpropiolic acid, 3107 2-Nonen-4,6,8-triyn-l-al, 3106 Octacarbondioxide pentamer, 3898 Octacarbondioxide tetramer, 3878 Octatetrayne-l,8-dicarboxyhc acid, 3229 Oligo(octacarbondioxide), 3103 1,3-Pentadiyne, 1819... 

Substituted oxazolidin-5-one derivatives, which are prepared from N -protected a-annino dicarboxyhc acids and paraformaldehyde, are employed for dual protection of the a-annino and a-carboxy groups in the synthesis of P-aspartyl and y-glutamyl esters (Scheme 4).Py For this purpose the oxazolidinone derivatives are synthesized by treatment of the Z amino acids with paraformaldehyde in a nnixture of acetic anhydride, acetic acid, and traces of thionyl chloride or by azeotropic distillation of the Z amino acids with paraformaldehyde and 4-toluenesulfonic acid in benzene. The resulting heterocychc compounds are readily converted into the tert-butyl esters with isobutene under acid catalysis. Esterification is achieved with tert-butyl bromidet or with Boc-F.P l Finally, the oxazolidinone ring is opened by alkaline hydrolysis or catalytic hydrogenolysis to yield the tert-butyl esters. 

The aramids, polyamides in which the amide bonds join aromatic rings, are one class of condensation polymer. Heating 1,4-benzenediamine and the acyl chloride of benzene-1,4-dicarboxyhc acid (terephthalic acid) gives the aramid Kevlar with loss of hydrogen chloride. 

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