A New, Improved and Convenient Synthesis of 4H-Cyclopenta[2,1-b:3,4-b′]-dithiophen-4-one

Abstract

A new and efficient three-step synthesis of 4H-cyclopenta[2,1-b:3,4-b¢]dithiophen-4-one (CDT) (1) is described. This was achieved by a one-pot, regiospecific synthesis of bis(2-iodo-3-thienyl)methanol (13), its subsequent oxidation to the bis(2-iodo-3thienyl) ketone (14) which after Ullmann coupling yielded the title compound 1.

Synthesis of Spiro[cyclopenta[1,2-b:5,4-b′]DiThiophene-4,9′-Fluorenes] SDTF dissymmetrically functionalized

“…9 After bromination of the starting derivative in 72% yield using NBS, 10 compound 1, was reacted with the Grignard reagent of 2-bromobiphenyl affording the corresponding carbinol 2 in 79% yield. The latter was finally engaged in a cyclization reaction in refluxing acetic acid with a catalytic amount of hydrochloric acid yielding SDTBr2F in 53% (Scheme 1).…”

Processible Cyclopentadithiophene Copolymers for Photovoltaic Applications

“…The electrochemical properties of these polymers were investigated by cyclic voltammetry. HOMO and LUMO values were taken at the onset of oxidation and reduction, respectively (28). As expected, these polymers had smaller HOMO values than their fluorene counterparts.…”

“…The bis(pinacol borate) monomer 3 was prepared by direct lithiation of 2 in THF, followed by quenching with 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane. The dibromide monomers 4m-7m were prepared according to published procedures (25)(26)(27)(28). The polymerization of 3 with monomers 4m-7m was carried out utilizing palladium(0)-catalyzed Suzuki coupling reactions utilizing equimolar amounts of the diboronic ester and dibromide monomers in hot toluene solutions using 2M Na 2 CO 3 as the aqueous base, resulting in the formation of dark red to purple hazy solutions.…”

Synthesis and characterization of donor–bridge–acceptor alternating copolymers containing perylene diimide units and their application to photovoltaic cells

“…2,7‐Dibromo‐9 H ‐carbazole ( 1 ),56 2‐decyltetradecylamine ( 5 ),57 4,4‐dioctyl‐4 H ‐cyclopenta[2,1‐b:3,4‐b′]dithiophene ( 8 ),58 4,4‐bis(2‐ethylhexyl)‐4 H ‐cyclopenta[2,1‐b:3,4‐b′]dithiophene ( 9 ),50 and N ‐9′‐heptadecanyl‐2,7‐dibromocarbazole ( M4 )45 were prepared according to reported procedures. PCBM was purchased from Nano‐C.…”