Naphtho triazine derivatives

Intramolecular carbenoid and nitrenoid insertions are also quite effective for the preparation of peri-condensed heterocycles. Thus, photolysis of 1-naphthyl-1,2,3-triazoles 113 leads to bcnzo[d,e quinolines 115, possibly via carbene intermediate 114 (Scheme 55) <1987J(P1)413>. Similarly, on photolysis or thermolysis of 8-azido-l-arylazonaphtha-lenes 116 naphtho[l,8-<7, ]triazine derivatives 117 are formed along with A-aryhminobenzo[/y/]indazoles 118 (Scheme 56) <1978JOC2508, 1982JOC1996>. 

Naphtho[l,8-de][l,2,3]triazine 114 can be alkylated with a variety of alkyl halides and lithium diisopropylamide (LDA) to give alkylated derivatives 115. Reduction of 115 with aluminium amalgam cleaves the naphthotriazine moiety to afford substituted a-aminoacids 116 in good overall yields <00TL6665>. 

Alkylation of l/f-naphtho[l,8-de]triazine (32, R = H) was originally believ to proceed exclusively at Nj, but this is now known to be incorrect. Perkins showed in 1964 that treatment of 32, R = H, with either dimethyl or diethyl sulfate in ethanolic sodium hydroxide gives a 1 1 mixture of the N,- and Nj-derivatives 32, R = Me, Et, and 132, R = Me, Et, respectively. The structure of 132, R = Me, followed largely from... 

As shown in Section II,C,l,b, photolysis or thermolysis of l-azido-8-arylazonaphthalenes gives rise to heterocyclization of these compounds, resulting in a mixture of mesoionic derivatives of naphtho[rf ]triazine 233... 

The most interesting compounds described in this paragraph are meso-ionic naphtho[reactions with olefinic compounds. For instance, the reaction with acetylenedicarboxylates gives rise to adducts 458, which are dehydrogenated spontaneously to the new heteroaromatic systems 459 with the aromatic 147r-electron contour [75JCS(PI)556]. 

Syntheses of perimidine 109 and naphtho[l,8-<7, ]triazine 110 derivatives usually start from 1,8-diaminonaphthalene by procedures which are quite similar to the synthesis of benzimidazoles and benzotriazoles from 1,2-diaminobenzene <1995AQ151>. For example, 2-alkyl and 2-arylperimi-dines 112 can be readily obtained in good yield by heating carboxylic acids with 1,8-naphthalenediamine 111 under microwave conditions (Scheme 54) <2005ASJ2411>. 

Naphtho[l,2-rf]thiazole (244) cyclocondensates with glyoxilic acid derivatives to give naphtho-[l, 2 4,5]thiazolo[3,2-i>][l,2,4]triazin-9-ones (245) (Equation (39)) <93JHC1331>. 

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