4112-89-4Relevant articles and documents
Evaluating aryl esters as bench-stable C(1)-ammonium enolate precursors in catalytic, enantioselective Michael addition-lactonisations
Young, Claire M.,Taylor, James E.,Smith, Andrew D.
supporting information, p. 4747 - 4752 (2019/05/24)
An evaluation of a range of aryl, alkyl and vinyl esters as prospective C(1)-ammonium enolate precursors in enantioselective Michael addition-lactonisation processes with (E)-trifluoromethylenones using isothiourea catalysis is reported. Electron deficient aryl esters are required for reactivity, with 2,4,6-trichlorophenyl esters providing optimal product yields. Catalyst screening showed that tetramisole was the most effective isothiourea catalyst, giving the desired dihydropyranone product in excellent yield and stereoselectivity (up to 90 : 10 dr and 98 : 2 er). The scope and limitations of this process have been evaluated, with a range of diester products being generated after ring-opening with MeOH to give stereodefined dihydropyranones with excellent stereocontrol (10 examples, typically ~90 : 10 dr and >95 : 5 er).
A convenient one-pot completely stereoselective synthesis of trans-4-Hydroxystilbenes and its derivatives and X-ray structure of its precursor
Chhor, Rakeshwar B.,Singh, Kunwar A.,Nosse,Tandon, Vishnu K.
, p. 2519 - 2530 (2007/10/03)
The synthesis of E-isomer of 4-Hydroxystilbene and its derivatives 3 by reductive elimination of the carbonyl function in 2-phenyl-1-(4-hydroxyphenyl)ethan-1-one and its derivatives 2 and the X-ray structure of 2a are described.