Synthesis of Selenophenes

Poly(3,4-ethylenedioxyselenophene)

“…To prepare PEDOS, we first developed a new and efficient synthetic strategy for the preparation of 3,4-ethylenedioxyselenophene (EDOS; 5 , Scheme ) . The selenophene ring was constructed, for the first time, by cycloaddition of 3 with freshly prepared SeCl 2 in the presence of NaOAc . Transetherification of 4 with ethylene glycol in the presence of a catalytic amount of p -toluenesulfonic acid ( p -TSA) produced EDOS (52% yield).…”

Recent Advances in the Synthesis of Selenophenes and Their Derivatives

“…The first protocols for the synthesis of selenophenes used as precursors hexane-2,5-dione and phosphorous pentaselenide (Paal, 1885) [ 125 ], metallic selenium and acetylene (Briscoe and Peel, 1928) [ 126 ], acetylenes and a mixture of bauxite and aluminum selenide (McMahon and co-workers, 1933) [ 127 ], acetylene with dimethyl selenide or diselenide (Voronkov and co-workers, 1987) [ 128 ], 2,4-alkadienic esters by oxidation reaction with SeO 2 (Takeda and co-workers, 1986) [ 129 ], among others [ 117 ], under high temperatures (180–600 °C). Since then, new protocols were developed for milder reaction conditions and that would afford selenophene derivatives in high yields.…”

“…Thus, considering the importance of the selenophene core, some reviews have been published during the last few decades that describe several strategies to access these compounds [ 117 , 118 , 119 , 120 , 121 , 122 , 123 ]. Among them, a short review was recently published [ 124 ] covering synthetic methods to access several selenophene derivatives, and the synthetic versatility of selenophenes in the formation of new C-C bonds.…”

The [3 + 2] cycloaddition reaction of thiazole carbene-derived C-C-Se 1,3-dipoles: a concise and highly efficient strategy for the construction of multifunctional dihydroselenophenes and selenopheno[2,3-b]pyrazines

“…The known methods for the construction of selenophenes are mainly based on the ring-closure reactions of acetylenes, olefins, b-diketo compounds and a,b-unsaturated acetonitriles with selenium reagents, including selenium chloride, sodium selenide, elemental selenium, or dimethyl diselenide (MeSeSeMe). 6,11 Preparation of aromatic ring fused selenophenes generally starts from intramolec-ular cyclization of selenium substituted aromatic compounds. 7,12 Although numerous syntheses of selenophene derivatives have been reported, further development of concise and efficient strategy for the construction of selenophenes and fused selenophenes is of great importance.…”