Improved addition of phenyllithium to hindered ketones by the use of non-polar media
作者:Vincent Lecomte、Elie Stéphan、Gérard Jaouen
DOI:10.1016/s0040-4039(02)00597-x
日期:2002.5
The use of a non-polar medium at room temperature is an efficient, cheap and easy way to improve the low reactivity of six hindered ketones towards phenyllithium.
在室温下使用非极性介质是一种有效,廉价和简便的方法,可以改善六种受阻酮对苯基锂的低反应性。
Cerium(III) chloride promoted addition of organometallic reagents to (−)-menthone—preparation of chiral neomenthyl derivatives †Dedicated to Professor Dr. Karl-Heinz Thiele on the occasion of his 70th birthday. †
作者:Stefan Panev、Vladimir Dimitrov
DOI:10.1016/s0957-4166(00)00087-2
日期:2000.4
The activation of (−)-menthone with anhydrous CeCl3 led to high yielding additions of different organometallic reagents. Products of exclusively equatorial-addition of the reagents were obtained; only PhMgBr yielded additionally ca. 5% of the axial-addition product.
Improved addition of organolithium reagents to hindered and/or enolisable ketones
作者:Vincent Lecomte、Elie Stéphan、Franck Le Bideau、Gérard Jaouen
DOI:10.1016/s0040-4020(03)00189-3
日期:2003.3
the addition of some aryl- and alkyllithium derivatives to somehindered and/or enolisable ketones in different solvents (polar and apolar) and, in some cases, at different temperatures and reaction times, will be presented here. The reversibility of the addition of aryllithium to these specific ketones will be observed and discussed. This approach is then used to prepare new steroids as precursor for
halogen-bond-assisted C–C activation of cyclic and acyclic alkanols in the absence of catalysts and oxidants, where the inexpensive N-haloimides act as bifunctional reagents to activate and halogenate alcohols. This redox-neutral protocol is a general method for the halogenation of the C–C bonds of primary, secondary, and tertiary alkanols, thus installing three types of halogen atoms and boronic esters