2351-97-5Relevant articles and documents
Isolation of intermediary anti-aldol adducts of the Horner-Wadsworth-Emmons reaction utilizing direct titanium-aldol addition and successive Br?nsted acid promoted stereoselective elimination leading to (Z)-α,β-unsaturated esters
Katayama, Mayumi,Nagase, Ryohei,Mitarai, Kumi,Misaki, Tomonori,Tanabe, Yoo
, p. 129 - 132 (2006)
The reagent TiCl4-Et3N was used in the Horner-Wadsworth-Emmons (HWE)-type reaction of triethylphosphonocarboxylates with aldehydes, wherein unstable intermediary aldol adducts were isolated with anti-selectivity. Subsequent Br?nsted acid promoted stereoselective elimination was successfully performed using TBS-benzamide-pyridinium triflate to give the less-accessible Z-α,β-unsaturated esters. Georg Thieme Verlag Stuttgart.
Stereoselective synthesis of α-methyl and α-alkyl ketones from esters and alkenes: Via cyclopropanol intermediates
Barysevich, Maryia V.,Kazlova, Volha V.,Kukel, Aliaksandr G.,Liubina, Aliaksandra I.,Hurski, Alaksiej L.,Zhabinskii, Vladimir N.,Khripach, Vladimir A.
supporting information, p. 2800 - 2803 (2018/03/21)
Alkenes bearing a stereocenter in the allylic position were found to undergo Kulinkovich hydroxycyclopropanation with good diastereoselectivity. For the isomerization of the resulting cyclopropanols to diastereomerically enriched α-methyl ketones, a new mild regioselective method has been developed. A sequence of stereoselective cyclopropanation and cyclopropanol ring opening was successfully employed for the construction of the C20 stereocenter in steroids.
Structural effects in pyrazolidinone-mediated organocatalytic Diels-Alder reactions
Gould, Eoin,Lebl, Tomas,Slawin, Alexandra M.Z.,Reid, Mark,Smith, Andrew D.
experimental part, p. 8992 - 9008 (2011/01/04)
A range of pyrazolidin-3-ones have been prepared and their activity as catalysts for iminium-ion promoted Diels-Alder reactions evaluated. Systematic variation of the C(5)- and N(2)-substituents indicates that the incorporation of an electron withdrawing
