Photocyclization of 1,2-diaryl- and photobicyclization of 1,2,6-triarylpyridinium cations

Alkylated Benzodithienoquinolizinium Salts as Possible Non-Fullerene Organic N-Type Semiconductors: An Experimental and Theoretical Study

“…Conversion of ( 2) into the corresponding N -aryl-2,6-bis(2-thienyl)-4-phenyl pyrydinium tetrafluoroborates 3a – c by reaction with 4-alkylanilines also followed a standard procedure, described in the literature [ 46 ]. The photocatalytic bicyclization of N -aryl-2,4,6-trisubstituted pyridinium salts has been previously described [ 47 ] and the procedure was adapted to the preparation of tetrafluoroborate salts 4a – c from the corresponding pyridinium salts 3a – c.…”

“…To the best of our knowledge, photocyclized pyridinium salts have never been proposed as potential n-type organic semiconductors. Their synthesis by photocyclization of readily obtained N-arylpyridinium salts has been described for more than thirty years [46,47]. More recently, some of their derivatives such as 2-phenyl-benzo [8,9]quinolizino [4,5,6,7-fed]-phenanthridinylium tetrafluoroborate (PQPBF 4 ) have been shown to form columnar π-stacked aggregates in the solid phase [48].…”

Synthesis of 5-Aryl-1,3-Dimethyl-7-Selenoxopyrimidino[4,5-d]Pyrimidine-2,4(1H,3H)-Dione

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Owing to the importance of pyrimidine derivatives, considerable attention has been devoted to their chemistry and biological activity. 1 In recent years, there has been increasing interest in their synthesis, and some methods allow access to a large number of multifunctionalised pyrimidine derivatives. [2][3][4][5] The current interest in selenium-containing organic compounds stems from their remarkable biological functions.

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“…A tentative mechanism for this transformation is proposed in Scheme 2. The reaction starts with formation of aroyl isoselenocyanate 5, followed by addition of 6-amino-N,N′dimethyluracil 1 to generate 6, subsequent cyclisation of which generates 7, which is converted into 4 by elimination of water and a [1,3]-H shift.…”

Synthesis of 2-Selanylidene-1,9A-Dihydro-2H-Pyrido[1,2-A]Pyrimidine Derivatives

“…[1][2][3][4] Since the isolation of pyrimidine derivatives, considerable attention has been devoted to their chemistry and biological activity. 5 The current interest in seleniumcontaining organic compounds stems from their remarkable synthetic and biological functions. [6][7][8][9][10] The first synthesis of acyl isoselenocyanates, which were generated by the reaction of acyl chlorides and potassium selenocyanate, was described by Douglas.…”