Anthranils ring expansion

Photolysis of anthranils (506) in methanol or amines gives 2-methoxy- or 2-amino-3//-azepines (507) by ring expansion of intermediate nitrenes (8iAHC(28)23l). Photolysis of 2-alkylindazoles... 

Anthranils undergo ring expansion to quinoline derivatives on treatment with various C-nucleophiles (see Scheme 17). 

TV-AlkylbenzMisoxazolium cations undergo base-catalyzed ring expansion to 1,3-benzoxazines (Section 3.4.3.12.3). Benzoxazinones are obtained by heating 3-acylanthranils (Section 3.4.3.4.4) or acylating anthranils (Section 3.4.1.8.6). 

The phenylhydrazone of IA (291), which is not available from IA directly, was synthesized via a ring expansion of the isatin 290 in the presence of CuCl2 (Eq. Zb).299 Reaction of the amino-substituted anthranilic hydrazide 104 with dimethyl acetylenedicarboxylate leads to the pyrazoloquinazolone... 

The addition products of IV-Boc anthranilic acid and IV-carboxy-a-amino add anhydrides (138) undergo ring expansion and decarboxylation on treatment in situ with HCl to give 1,4-benzo-diazepine-2,5-diones (139) (Scheme 23) <9479051 >. This reaction is interesting because no race-mization was observed. However, there was considerable racemization during the cyclisation of the isolated coupling product of iV-Boc anthranilic acid with an amino acid <93SC2265,9479051). 

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