Dimethylaminophenyl perchlorate

The photo-oxidation of the aryl-substituted cycloheptatrienes 7-(/ -methoxy-phenyl)cycloheptatriene and 7-, 1- and 3-(/ -dimethylaminophenyl)cycloheptatrienes to the corresponding radical cations in de-aerated acetonitrile solution was accomplished by electron transfer to the electronically excited acceptors 9,10-dicyanoanthracene, iV-methylquinolinium perchlorate, iV-methylacridinium perchlorate and l,T-dimethyl-4,4-bipyridinium dichloride. In the case of l- p-methoxyphenyl)cycloheptatriene (62), deprotonation of the radical cation occurs successfully, compared with back electron transfer, to give a cycloheptatrienyl radical (63) which undergoes a self-reaction forming a bitropyl. If the photooxidation is done in air-saturated acetonitrile solution containing HBF4 and one of the acceptors, the tropylium cation is formed. Back electron transfer dominates in the / -dimethylaminocycloheptatrienes and the formation of the cycloheptatrienyl radical is prevented. 

Figure 1 The absorption spectra of (4-(4-dimethylaminophenyl)-2,6-diphenyl-thia-pyrylium perchlorate) in dichoromethane, a homogeneous film of the perchlorate compound in bisphenol-A polycarbonate, and the aggregated dye produced by exposing the homogeneous film to dichloromethane vapors.

Figure 2 The spectral dependence of the xerographic gain of a mixture of (4-(4-dimethylaminophenyl>2,6-diphenylthiapyrylium perchlorate), bisphenol-A polycarbonate, and a triarylmethane donor TPM before and after aggregation by fuming with dichloromethane.

The 3-methylimino 1,2-benzisothiazole 150, which in solution is in equilibrium with 2-methyl benzisothiazole 151, reacted with concentrated tetrafluoric and nitric acids to produce 3-benzensulfonylazo-2-methyl-l,2-benzisothiazolium tetrafluo-roborate 152 in quantitative yield. This salt 152 was treated with A A -dimethyl-aniline to give 2-methyl-3-[4-(l-dimethylaminophenyl)azo]-l,2-benzisothiazolium perchlorate 153 in 63% yield (71LA46, Scheme 51). 

The kinetics of the diazotization of 4-aminopyridine in 0.0025-5.0 M perchloric acid were studied, and the reaction was believed to proceed by only one mechanism whose kinetic form is first order with respect to the amine as well as to nitrous acid. The rate of the reaction showed an exponential catalytic dependence on the concentration of added perchloric acid and sodium perchlorate. In solutions of constant ionic strength the rate was directly related to the acidity function Hq). The 4-diazonium ion was characterized as 4-(2-hydroxy-l-naphthylazo)pytidine. When 4-aminopyridine is diazotized and treated with Ar,7 A-dimethylaniline, 4-(p-dimethylaminophenylazo)pyridine (DC-95) is obtained. 2-(p-Dimethylaminophenyl)pyridine is isolated when 2-aminopyridine is used instead of 4-aminopyridine. ... 

C17H18N2O2S, N,N -Diacetyl-3-methylthiobenzidine, 46B, 92 C17H18N2O4, Dimethyl 4,4 -methylenebis(phenylcarbamate), 46B, 93 Cl7H19N3O6S, p-Dimethylaminophenyl N-methyl-N-(p-nitrophenylsulphon-ylmethyl)-carbamate, 44B, 92 C17H2 2ClN30i, Auramine perchlorate, 32B, 100... 

The thiapyrylium salt, 4-(4 -dimethylaminophenyl)-2,6-diphenylthiapyrylium perchlorate (XXIV), is the most mentioned compound in its class. It was synthesized by first condensing p-dimethylaminobenzaldehyde with 2 equivalents of acetophenone in perchloric acid to form a pyrylium perchlorate [251,252], followed by sulfiir-ization of the pyrylium perchlorate with sodium hydrosulfide to yield XXIV (Scheme 10.8) [253]. 

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