Synthesis of new polyconjugated molecules with biphenyl, dibenzothiophene, carbazole and phenanthrene units

Abstract

The simple methods of synthesis of hardly accessible substituted biphenyl, dibenzothiophene, carbazole and phenanthrene derivatives were elaborated starting from dimethyl 4,4'-biphenyldicarboxylate. The series of new luminophores with extended π-conjugated chains based on combinations of biphenyl, carbazole, dibenzothiophene, phenanthrene fragments and alternating phenyl, vinyl or heterocyclic units were synthesized by the Wittig and the Knoevenagel reactions of corresponding aromatic dialdehydes and different CH-acids or phosphonium salts. Investigation of the effect of various substituents on the luminescent properties has been presented. The new luminophores could be used as emissive or charge transport layers in organic light emitting diodes (OLEDs).

Synthesis of Tetracyclic 2,3-Dihydro-1,3-diazepines from a Dinitrodibenzothiophene Derivative

“…Simultaneous cyclization and acidic hydrolysis of dimethyl biphenyl-4,4′-dicarboxylate 1 was achieved in refluxing chlorosulfonic acid according to the procedure of Olkhovik et al to produce diacid 2. 50 In the same report, mononitration of 2 at the 1-position was performed; therefore, by using the more concentrated fuming nitric acid and extending the reaction time, dinitration was achieved to produce 1,9-dinitrodibenzothiophene-5,5-dioxide-3,7-dicarboxylic acid 3. A byproduct containing a nitro group in the 2-position was reported for the mononitration; 50 however, we did not observe this during our dinitration process.…”

“…5,5-Dioxo-5H-dibenzo[b,d]thiophene-3,7-dicarboxylic Acid (2). 50 A solution of dimethyl biphenyl-4,4′-dicarboxylate 1 (5.00 g, 19.0 mmol) in chlorosulfonic acid (20 mL) was heated at reflux for 3 h. The reaction mixture was cooled to room temperature and poured over ice to precipitate the product. The white precipitate was filtered and washed with water (50 mL), hexane (40 mL), and diethyl ether (40 mL).…”

Immobilisation of a molecular epoxidation catalyst on UiO-66 and -67: the effect of pore size on catalyst activity and recycling

“…The compound was prepared similar to the literature-known procedure. 37 A mixture of nitric acid (56%, 1.3 mL, 74 mmol) and concentrated sulfuric acid (1.6 mL) was added dropwise to a solution of dimethylbiphenyl-4,4′-dicarboxylate (5 g, 74 mmol) in 50 mL of concentrated sulfuric acid at 0 °C under intense stirring. The reaction mixture was maintained at 0-5 °C for 1 h and at 10-15 °C for 4 h before being poured on crushed ice.…”

Synthesis and post-synthetic modification of amine-, alkyne-, azide- and nitro-functionalized metal–organic frameworks based on DUT-5

“…The first key intermediate, dimethyl 2-nitrobiphenyldicarboxylate (1), was prepared by nitration of Me 2 BPDC following a described procedure under standard nitration conditions. 56 The nitrofunctionalized linker H 2 nitroBPDC was obtained by hydrolysis of the ester groups of (1) under basic conditions. The second key intermediate of the synthesis, dimethyl 2-aminobiphenyldicarboxylate (2), was prepared by reduction of (1) with Pd/C in H 2 atmosphere.…”