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A method of synthesizing 6(7)-aminoperimidines has been developed based on the electrophilic amination of perimidines with sodium azide in PPA. The corresponding amides were synthesized by acylation and were also obtained by the Schmidt reaction from 6(7)-acetyl(or benzoyl)perimidines. A special feature of the structure of the 2-substituted amines and amides is the presence of annular tautomerism slow in NMR time.Aromatic amines serve as important synthetic building blocks. The standard method of synthesizing them is sequential nitration and then reduction of the nitro compound formed at the first stage [1]. Direct onestep amination is known, however it proceeds only in low yield [1,2], since in many cases the initial aromatic compound is used as solvent. Hydroxylamine [3,4], alkylhydroxylamines [5], hydroxylamine O-sulfonic acid [6], and hydrazoic acid [7] in the presence of a Lewis acids are used as aminating reagents. More recently Olah has used hydrazoic acid [8] and trimethylsilyl azide [9] in the presence of a superacid for these purposes. The latter system is the most efficient, the yield was ~90% calculated on azide, but as a result of using a large excess of aromatic compound the degree of conversion of the latter does not exceed 10%.In the present work we propose a method of aminating perimidines based on a new reactant system, sodium azide -PPA (for preliminary communication see [10]).We have proposed that the PPA azide 1 will be formed as a result of the reaction of sodium azide with PPA, which may be protonated both at the nitrogen atom a and also b with the formation of two tautomeric cations 2. As the result of azocoupling of the latter with perimidines 3a-c the intermediates 4a-c will be formed, the hydrolysis of which leads to a mixture of tautomers of amines 5a-c and 6a-c.

A new method for the synthesis of 4H-benzo [de]isoquinolin-4-ones has been developed, based on the reaction of 2-naphthyl ethers with an equimolar quantity of 1,3,5-triazines in polyphosphoric acid. With a 2.5 molar excess of 1,3,5-triazines in polyphosphoric acid, the products of 1,6-diacylation (diformylation) are formed. Isoquino[6¢,5¢,4¢:10,5,6]anthra [2,1,9-def]isoquinoline is formed upon reaction of a 1.5 molar excess of 1,3,5-triazine with naphthalene in polyphosphoric acid at 130-140°C.The monoacylation of naphthalene derivatives has already become a very well studied classic reaction. In contrast, there are few examples of the diacylation and diformylation of naphthalene derivatives. 1 It is well known that 1,3,5-triazine can undergo ring cleavage upon treatment with nucleophilic reagents and serve as a formyl group precursor. This property has been extensively used in organic synthesis. 2 Thus, formamidines, 2a perimidines, 2b benzimidazoles, 2b benzothiazoles, 2b benzoxazoles, 2b purines, 2b pyridines, 2c,d pyrimidines 2c,e,f and 1,6-naphthyridines 2g-i have been obtained utilizing different nucleophiles in reactions with 1,3,5-triazine (3a).Recently, we have reported the new reagent system of 1,3,5-triazines in polyphosphoric acid and have proved its effectiveness for the acylation and formylation of perimidine 3a,b and substituted naphthalenes, 3c and the peri-annelation of carbocyclic 3d and pyridine rings. 3e In the present paper we suggest methods for pyridine ring annelation to naphthalenes and regioselective 1,6-diacylation (diformylation) of 2-naphthyl ethers.On the basis of our previous work, 3 we propose that in the case of the reaction of 1,3,5-triazines with naphthalene and its monosubstituted derivatives, an intermediate 4 is formed, which is opened as for azanaphthalenes and in the series of subsequent transformations gives off the cation 7 (Scheme 1).The behavior of cations 7a-d depends on the nature of X. As a result of hydrolysis, dicarbonyl compounds (e.g., 8)or 4H-benzo [de]isoquinolin-4-ones 9a,b (if X = OR¢) may be formed (Scheme 2). Scheme 2 Hydrolysis of cations 7a-d

Methods have been developed for the synthesis of 1,3,6,8-tetraazapyrene based on the reaction of 1,4,5,8-tetraaminonaphthalene with formic acid [1] and the synthesis of 2,7-dimethyl-1,3,6,8-tetraazapyrene based on the reaction of 6,7-diamino-2-methylperimidine with acetic anhydride [2]. These methods involve the use of not readily available starting reagents and are not general. In the present work, we propose a method for the synthesis of such compounds from available perimidine ketones 1a-c. Heating ketone 1a-c (1 mmol) and NaN 3 (0.26 g, 4 mmol) in PPA (2-3 g) at 70-80°C for 1 h and then at 100-110°C for 4 h with monitoring by thin-layer chromatography leads to 1,3,6,8-tetraazapyrenes 4a-c in 31-44% yield. The PPA sample containing 87% P 2 O 5 was prepared according to Uhlig [3].This reaction involves the intermediate formation of amides 2a-c, whose amination using sodium azide in PPA, as previously described for perimidines [4,5], leads to dihydro derivatives 3a-c, which are oxidized by atmospheric oxygen to give tetraazapyrenes 4a-c. 1-4 a R = R 1 = Me, b R = R 1 = Ph, c R = Ph, R 1 = Me

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