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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.

In previous work [1][2][3][4], we have developed a number of methods for the peri annelation of six-membered rings to give perimidines. In light of the high biological activity of a significant number of indole derivatives, we propose a method for the peri annelation of the pyrrole ring to perimidines. The reaction of ketones 1a-c (1 mmol) and NaN 3 (0.07 g, 1.08 mmol) in PPA* (2-3 g) at 70-80°C for 1 h and then at 150-160°C for 4 h monitored by thin-layer chromatography leads to 1H-1,5,7-triazacyclopenta[c,d]phenalenes 3a-c in 36-48% yield.The reaction involves intermediante formation of amides 2a-c, which cam be isolated, for example 2a.The 1 H NMR spectra were taken on a Bruker WP-200 spectrometer at 200 MHz in DMSO-d 6 with TMS as the internal standard. The reaction course and purity of the products obtained were monitored on Silufol UV-254 plates with 1:1 ethyl acetate-ethanol as the eluent. NH N R O R 1 NH N R N H R 1 O N N R N H R 1 1a-c NaN 3 ∆ 2a-c 3a-c PPA 1-3 a R = H, R 1 = Me, b R = R 1 = Me, c R = Me, R 1 = Ph _______ *The PPA sample used containing 86% P 2 O 5 was prepared according to Uhlig [5].

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