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Hajos
Hajos could be: *The Hajos–Parrish–Eder–Sauer–Wiechert reaction in organic chemistry * Zoltan Hajos (1926–2022), Hungarian-American organic chemist * Hajós, a town in Bács-Kiskun county, Hungary {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoltan Hajos
Zoltan George Hajos (born Zoltán György Hajós; 3 March 1926 – 9 October 2022) was a Hungarian-American organic chemist. Originally an academic in his native Budapest, then an industrial chemist in the pharmaceutical industry, he is known for the Hajos–Parrish–Eder–Sauer–Wiechert reaction (originally named Hajos-Parrish reaction by Claude Agami in 1985). Biography Chemistry training Hajos studied chemistry at the Technical University of Budapest (TU Budapest), in Hungary, completing an M.Sc. in 1947, and his doctoral work under Zoltan Csuros of the Institute of Organic Chemical Technology in 1950. Early academic career Hajos remained there until accepting a position as assistant professor in organic chemistry at the TU Budapest in 1948, where he stayed until 1957, With backlash following the 1956 ''Revolution'' in October, 1956, Hajos left TU Budapest and communist Hungary for the United States, where he took a position as a research associate in organic chemistr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hajos–Parrish–Eder–Sauer–Wiechert Reaction
The Hajos–Parrish–Eder–Sauer–Wiechert reaction in organic chemistry is a proline catalysed asymmetric aldol reaction. The reaction is named after its principal investigators, Zoltan Hajos others, from Hoffmann-La RocheZ. G. Hajos, D. R. Parrish, German Patent DE 2102623 1971 and Schering AG. Discovered in the 1970s the original Hajos-Parrish catalytic procedure – shown in the reaction equation, leading to the optically active bicyclic ketol – paved the way of asymmetric organocatalysis. The Eder-Sauer-Wiechert modification lead directly to the optically active enedione, through the loss of water from the bicyclic ketol shown in figure. It has been used extensively as a tool in the synthesis of steroids and other enantiomerically pure molecules. In the original reaction shown in the figure above naturally occurring chiral proline is the chiral catalyst in an Aldol reaction. The starting material is an achiral triketone and it requires just 3% of proline to obtain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
