81770-72-1Relevant articles and documents
Direct asymmetric α-hydroxylation of 2-hydroxymethyl ketones
Paju, Anne,Kanger, T?nis,Pehk, T?nis,Lopp, Margus
, p. 7321 - 7326 (2007/10/03)
A direct α-hydroxylation of racemic 2-hydroxymethyl ketones with the Sharpless epoxidation catalyst resulted in α,β-dihydroxy ketones in high ee (up to 97%) and in moderate to good isolated yield (up to 58%).
Use of Protected β-Bromocyclopentenones and β-Bromocyclohexenones as β-Acylvinyl Anion Equivalents
Shih, Chuan,Swenton, John S.
, p. 2825 - 2832 (2007/10/02)
Ethylene glycol ketals of the 3-bromocyclohex-2-en-1-one as well as its 2-methyl, 2-n-propyl, and 5,5-dimethyl derivatives have been prepared, and their reactions with butyllithium were studied.The organolithium reagents derived from the above compounds react with a variety of electrophiles to afford after acid hydrolysis the corresponding 3-substituted cyclohexenones.Attempts to prepare the ethylene glycol ketal of 2-methyl-3-bromocyclopent-2-en-1-one gave a low yield of the bromoketal.However, dithioketals of 3-bromocyclopent-2-en-1-one and its 2-methyl derivativecould be prepared in good yield.The metalation chemistry of the dithioketals in both the five- and six-membered-ring series was examined.The functionalization chemistry of the resulting organolithium compounds afforded after dithioketal hydrolysis 3-functionalized cyclohex-2-en-1-ones and cyclopent-2-en-1-ones.Several limitations of the chemistry using allyl bromide and cyclohexenone as electrophiles are noted.
