14066-85-4Relevant articles and documents
The effect of organic cations on the electronic, optical and luminescence properties of 1D piperidinium, pyridinium, and 3-hydroxypyridinium lead trihalides
Bahnemann, D. W.,Emeline, A. V.,Kevorkyants, R.,Rozhkova, Yu. A.,Selivanov, N. I.
, p. 4390 - 4403 (2020)
We present a structural and optoelectronic study of 1D piperidinium, pyridinium, and 3-hydroxypyridinium lead trihalides. In contrast to the piperidinium and pyridinium species whose single inorganic chains [PbX31-]n are separated by organic cations, the 3-hydroxypyridinium compound is characterized by double inorganic chains. According to DFT the valence and conduction bands of the piperidinium lead trihalides are composed of occupied p-orbitals of the halogen anions and unoccupied p-orbitals of the Pb2+ cations. In contrast, the pyridinium species feature low-lying cationic energy levels formed from the cation's π?-orbitals. Thus, electronic transitions between the cationic energy levels and valence bands require less energy than valence to conduction band transitions in the case of piperidinium lead trihalides. The presence of an OH group in the pyridinium ring leads to a bathochromic shift of the cationic energy levels resulting in a decreased energy of transitions from the cationic energy levels to the valence band. Electronic transitions predicted by DFT are observable in experimental optical absorption and luminescence spectra. This study paves the way for creation of 1D perovskite-like structures with desired optoelectronic properties.
Sequential substitution/ring cleavage/addition reaction of 1-(cyclohex-1-enyl)-piperidine and -pyrrolidine with chloropyruvates for the efficient synthesis of substituted 4,5,6,7-tetrahydro-1H-indole derivatives
Mamedov, Vakhid A.,Hafizova, Elena A.,Zamaletdinova, Anastasiya I.,Rizvanov, Il'dar Kh.,Mirgorodskaya, Alla B.,Zakharova, Lucia Ya.,Latypov, Shamil K.,Sinyashin, Oleg G.
, p. 9143 - 9153 (2015/11/09)
Sequential substitution/ring cleavage/addition reaction of 1-(cyclohex-1-enyl)-piperidine and -pyrrolidine with chloropyruvates has been accomplished for the synthesis of various polysubstituted 4,5,6,7-tetrahydroindoles. This one-pot, general and highly regioselective method avoids harsh conditions and expensive catalysts. It proceeds with high atom-efficiency and shows a broad substrate scope and functional group tolerance, making it a highly practical approach for the preparation of various tetrahydroindole derivatives. A family of 17 tetrahydroindoles was synthesized in good yields, which is indicative of the general character of this reaction. 10 of the tetrahydroindole derivatives with various substituents were successfully transformed into the corresponding indoles. This methodology allows access to indoles bearing ω-halo- (mostly chloro-)butyl and pentyl substituents at the nitrogen atom (by variation of enamines) and at the C2, C3 positions (by variation of pyruvates, including bromoaryl and chloroalkyl derivatives). The reaction can be used in conjunction with enamine synthesis offering a practical three-component heteroannulation methodology to produce 4,5,6,7-tetrahydroindoles from cyclohexanone, pyrrolidine and arylchloropyruvates.
EFFECT OF THE STRUCTURE OF AMINES ON RATE AND MECHANISM OF THEIR REACTIONS WITH 2-(β,β-DIBROMOVINYL)-5-NITROFURAN IN ACETONITRILE
Kravchenko, V. V.,Kotenko, A. A.,Popov, A. F.,Kostenko, L. I.,Vegh, D.,Kovac, J.
, p. 2140 - 2143 (2007/10/02)
The kinetics of the reaction of 2-(β,β-dibromovinyl)-5-nitrofuran with alkylamines of various types (primary, secondary, and tertiary) in acetonitrile at 55 deg C were studied.It was shown that enamines are formed quantitatively in the case of the reactions with secondary amines.At the same time the products from the reactions with primary amines are the corresponding amidines.Here the monosubstitution product is formed at the first stage, as in the case of the reactions with secondary amines, and rearranges to the imidoyl halide with subsequent substitution of the halogen atom at the imidoyl carbon atom.A quantitative assessment is made of the effect of the structure of the enamine on the rate of the processes.
