Scope and Limitations of Lithium-Ethylenediamine-THF-Mediated Cleavage at the α-Position of Aromatics: Deprotection of Aryl Methyl Ethers and Benzyl Ethers under Mild Conditions
作者:Takeshi Sugai、Takeyuki Shindo、Yasuaki Fukuyama
DOI:10.1055/s-2004-815977
日期:——
and limitation of lithium-ethylenediamine-THF-mediated reductive bond cleavage at the α-position of aromatics were examined. Very mild conditions such as lithium metal (5 equiv) and ethylenediamine (7 equiv) in oxygen-free THF were quite effective for the demethylation of aromaticethers even at as low as -10 °C. Allyl benzyl ethers were also deprotected under these conditions with very little change
INTERNAL OLEFINIC SULFONATE COMPOSITION AND CLEANSING COMPOSITION CONTAINING THE SAME
申请人:KAO CORPORATION
公开号:US20140080751A1
公开(公告)日:2014-03-20
Provided is an internal olefin sulfonate composition which is capable of exerting good foamability at the same time with foam quality, foam dissipation property, and less irritation to the skin at high levels, and a cleansing composition containing the same.
The internal olefin sulfonate composition of the present invention comprises (A) an internal olefin sulfonate having 16 carbon atoms and (B) an internal olefin sulfonate having 18 carbon atoms, wherein a mass content ratio (A/B) of component (A) to component (B) is from 75/25 to 90/10.
Provided are an internal olefin sulfonate composition which is capable of sufficiently enhancing foamability, light foam quality, and instantaneous foam dissipation property, and a cleansing composition containing the internal olefin sulfonate composition. The internal olefin sulfonate composition comprises (A) an internal olefin sulfonate having 12 carbon atoms and (B) an internal olefin sulfonate having 14 carbon atoms, wherein a content mass ratio of the component (A) to the component (B), (A/B), is from 10/90 to 90/10, and a total content of the component (A) and the component (B) in the internal olefin sulfonate is from 60 to 100% by mass.
Cobalt-Catalyzed Isomerization of 1-Alkenes to (<i>E</i>)-2-Alkenes with Dimethylphenylsilylmethylmagnesium Chloride and Its Application to the Stereoselective Synthesis of (<i>E</i>)-Alkenylsilanes
“Co”axing selectivity into isomerization: Treatment of 1‐alkenes with dimethylphenylsilylmethylmagnesium chloride in the presence of a cobalt‐NHC complex in dioxane at 50 °C or higher provides the corresponding (E)‐2‐alkenes selectively. The isomerization is applicable to the stereoselective synthesis of (E)‐crotylsilanes and (E)‐1‐propenylsilanes from the corresponding homoallylsilanes and allylsilanes
Method for Determining Double-Bond Positions in Mixtures of Linear Olefins
作者:Jeffrey C. Gee、Daniel S. Prampin
DOI:10.1021/ac802449x
日期:2009.2.15
We describe a new method for estimating the positions of double bonds in mixtures of linear olefins longer than octene. The method requires about a gram of olefin and a 5−10 min reaction catalyzed by a homogeneous metathesis catalyst. The carbon number distribution of the product mixture, as determined by gas chromatography, depends upon the distribution of double-bond isomers in the starting mixture. We describe a computer algorithm for using the final carbon number distribution to determine the locations of double bonds in the starting mixture. Examples are based on tetradecenes, hexadecenes, and octadecenes.