Synthesis and Production
Reflecting their high stabilities, thiophenes arise from many reactions involving sulfur sources and hydrocarbons, especially unsaturated ones, e.g. acetylenes and elemental sulfur, which was the first synthesis of thiophene by Viktor Meyer in the year of its discovery. Thiophenes are classically prepared by the reaction of 1,4-diketones, diesters, or dicarboxylates with sulfiding reagents such as P4S10. Specialized thiophenes can be synthesized similarly using Lawesson's reagent as the sulfiding agent, or via the Gewald reaction, which involves the condensation of two esters in the presence of elemental sulfur. Another method is the Volhard-Erdmann cyclization.
Thiophene is produced on a scale of ca. 2M kg per year worldwide. Production involves the vapor phase reaction of a sulfur source, typically carbon disulfide, and butanol. These reagents are contacted with an oxide catalyst at 500–550 °C.
Read more about this topic: Thiophene
Famous quotes containing the words synthesis and/or production:
“It is in this impossibility of attaining to a synthesis of the inner life and the outward that the inferiority of the biographer to the novelist lies. The biographer quite clearly sees Peel, say, seated on his bench while his opponents overwhelm him with perhaps undeserved censure. He sees him motionless, miserable, his head bent on his breast. He asks himself: “What is he thinking?” and he knows nothing.”
—Andre Maurois (1885–1967)
“Just as modern mass production requires the standardization of commodities, so the social process requires standardization of man, and this standardization is called equality.”
—Erich Fromm (1900–1980)