19878-97-8Relevant articles and documents
Organoaluminum-catalyzed rearrangement of epoxides a facile route to the synthesis of optically active β-siloxy aldehydes
Maruoka, Keiji,Ooi, Takashi,Nagahara, Shigeru,Yamamoto, Hisashi
, p. 6983 - 6998 (2007/10/02)
A new, stereocontrolled rearrangement of epoxy silyl ethers leading to β-siloxy aldehydes has been effected with stoichiometric use of exceptionally bulky, oxygenophilic methylaluminum bis(4-bromo-2,6-di-trert-butylphenoxide) (MABR) under mild conditions. Used in combination with the Sharpless asymmetric epoxidation of allylic alcohols, this rearrangement represents a new approach to the synthesis of various optically active β-hydroxy aldehydes, useful intermediates in natural product synthesis. The modified organoaluminum reagent, MABR is also applicable to the transformation of a variety of simple epoxides to carbonyl compounds with high efficiency and selectivity. Further, the catalytic version for the rearrangement of epoxy silyl ethers as well as simple epoxides has been newly devised. The scope and limitation of this catalytic method has been clarified with various epoxy substrates.
Enantioselective Diastereospecific Synthesis of anti-α-Alkyl-β-hydroxy Esters through Cuprate Opening of Glycidic Esters
Mulzer, Johann,Lammer, Ortrud
, p. 2178 - 2190 (2007/10/02)
A diastereospecific chain elongation of the aldehydes 1 to anti-αalkyl-β-hydroxy esters 2 via the intermediates 4 - 7 is described.By means of the Sharpless epoxidation, 2 may be obtained with >90percent ee in either enantiomer.
