Aminophenyl ketone derivatives

Patent Aminophenyl Ketones Derivatives and a Method for the Preparation... 

Amidines 9 with an appropriate ortho-carbonyl substituent, which are obtained from the respective ortho-carbonyl aniline derivatives and 0-ethyl succinimide (5-ethoxy-4,5-dihydro-3//-pyrrol-2-one), are cyclized with sodium in alcohol to quinazolin-4(3// )-ones 10a and quinazolines 10b with a 2-[(alkoxycarbonyl)ethyl] substituent at C2. The reaction can also be carried out starting from anthranilates or 2-aminophenyl ketones as a simple one-pot synthesis. ... 

Synthesis and Properties. Polyquinolines are formed by the step-growth polymerization of o-aminophenyl (aryl) ketone monomers and ketone monomers with alpha hydrogens (mosdy acetophenone derivatives). Both AA—BB and AB-type polyquinolines are known as well as a number of copolymers. Polyquinolines have often been prepared by the Friedlander reaction (88), which involves either an acid- or a base-catalyzed condensation of an (9-amino aromatic aldehyde or ketone with a ketomethylene compound, producing quinoline. Surveys of monomers and their syntheses and properties have beenpubhshed (89—91). 

The N-acyliminium ion cyclization method for the synthesis of nitrogen heterocycles, developed by Speckamp and his collaborators, has also been applied to the synthesis of the vindorosine intermediate 529 (315). In this synthesis, the imine 531, derived from 3-(o-aminophenyl)-N-benzylsuccini-mide, was cyclized by base and acetylated to give 532, which was partially reduced to give the substrate 533 for N-acyliminium cyclization. Treatment of 533 with acid then gave the tetracyclic enol ester 534, which was converted into the target tetracyclic amino ketone 529a by obvious methods (Scheme 61) 315). 

This approach was described in CHEC-I as of importance only for the synthesis of cinnolines <84CHEC-i(3B)i>. Most of the examples given involve the insertion of nitrogen as the sixth atom by diazotization of o-aminophenyl derivatives, in which the ortho substituent is generally an alkene, alkyne, or enolisable ketone. Another example is the synthesis of 3-substituted-4(l//)-cinnolinones via diazotisation of o-aminophenylalkynes (Scheme 90) the precursor is readily made by palladium and copper iodide catalysis <89H(29)1255>. 

Thus, an efficient synthesis for stracturally diverse 4-(benzimidazol-2-yl) quinolines via reactions of 3-(2-aminophenyl)quinoxalin-2(l//)-ones and ketones, including acetone, acetophenones, 1,3-pentanedione and ethyl acetoacetate has been developed. The selective formation of the very different quinoline derivatives... 

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