N. N. Suvorov

Synthesis and photochromic properties of indolinospirochromenes with benzyl, ethyl, and acetonyl groups attached to the nitrogen atom

A number of photochromic indoline spirochromenes with benzyl, acetonyl, and ethyl substituents attached to the nitrogen atom in the indoline part of the molecule were synthesized. The introduction of a benzyl group at the nitrogen atom in place of a methyl group does not change the rate constants of the dark decolorization of the photomerocyanines, whereas an acetonyl group increases them, and an ethyl group decreases them. The introduction of the indicated substituents in the 1 position gives rise to a bathochromic shift (up to 18 nm) of the long-wave absorption band of the merocyanine form of the spirochromene.

Indole derivatives: XCVI. Synthesis and tuberculostatic activity of some 3-arylazoindoles

I H Z-.~F_// In o rde r to charac te r i ze compounds ff-XXVII), the i r IR and UV spec t ra were recorded. The IR spect r a showed the vN_ H band at 3490-3495 cm -I in solutions, which underwent a bathoehromic shift in paraffin oil to 3300-3400cm -1 (because of the format ion of in te rmolecular hydrogen bonds), the absorpt ion of an a romat ic sys tem (1450, 1600, and 3030 cm-l) , and a s t rong peak at 1400 =~ 20 cm -i due to the s t re tching vibrations of a N N bond in a t r a n s a r y l a z o compound [3]. Features of the UV spec t ra are given in Table 1.

Synthesis of 4-nitro-3,3,7-trimethyl-2-(2-hydroxystyryl)indolenines

The previously unknown hydroxystyrylindolenines have been synthesized by the direct condensation of 4-nitro-2,3,3,7-tetramethylindolenine with substituted salicylaldehydes. The structure of the prepared compounds has been confirmed by spectroscopic investigation.

Thermal and photostability of 5′,7′-dialkoxy-5,6′-dinitro-1,3,3-trimethylspiro(lndolin-2,2′-[2H]chromenes)

Some photochromic indoline spiropyrans have been synthesized and their thermal and photostability examined in films and in solution. Introduction of the NO2 group into the indoline moiety of the molecule stabilizes the spiropyran form in solution and in films, but blocking the NO2 group in the pyran moiety by adjacent alkoxy groups enhances the light stability of the compounds.

Synthesis and spectral characteristics of photochromic spirochromenes-2,3-dihydro-1H-pyrrolo[3,2-h]quinoline derivatives

Photochromic spirochromenes that differ from the standard indoline spirochromenes with respect to an angularly annelated pyridine ring were synthesized from 8-hydrazinoquinoline. The spectral characteristics of the merocyanine form of the compounds practically coincide with the characteristics of the analogous spirochromenes containing an annelated benzene ring.