N Alkylation of Tosylamides Using Esters as Primary and Tertiary Alkyl Sources: Mediated by Hydrosilanes Activated by a Ruthenium Catalyst
作者:Takashi Nishikata、Hideo Nagashima
DOI:10.1002/anie.201201426
日期:2012.5.29
Select your group: Either a primary or tertiaryalkyl group can be selectively introduced onto the nitrogen atom of tosylamides in a ruthenium‐catalyzed reaction employing hydrosilanes through a judicious choice in the esters that serve as the alkylsource (see scheme; Ts= 4‐toluenesulfonyl). These N‐alkylation reactions are useful for construction of naturally occurring azacyclic skeletons.
Diastereoselectivity of Enolate Anion Protonation. H/D Exchange of β-Substituted Ethyl Butanoates in Ethanol-<i>d</i>
作者:Jerry R. Mohrig、Robert E. Rosenberg、John W. Apostol、Mark Bastienaansen、Jordan W. Evans、Sonya J. Franklin、C. Daniel Frisbie、Sabrina S. Fu、Michelle L. Hamm、Christopher B. Hirose、David A. Hunstad、Thomas L. James、Randall W. King、Christopher J. Larson、Hallie A. Latham、David A. Owen、Karin A. Stein、Ronald Warnet
DOI:10.1021/ja962631s
日期:1997.1.1
The stereochemistry of base-catalyzed H/D exchange on 13 β-substituted ethyl butanoates in ethanol-d has been studied in order to analyze the steric and electronic factors which control the diastereoselectivity of electrophilic attack on enolate anions. Electrophilic deuteration of the enolate anion also determines the stereoselectivity of 1,4-conjugate addition of ethanol-d to α,β-unsaturated esters
Provided are a compound and a fragrance composition that are excellent in harmony with various other fragrance materials and can be blended to impart a natural and fresh floral feeling. The present invention provides a cyclopropane compound represented by Formula (I) and a fragrance composition containing a cyclopropane compound represented by Formula (I):
where R
1
is a methyl group and R
2
is a methyl group, or R
1
is a hydrogen atom and R
2
is an ethyl group.
Polymerizable composition, optical material comprising the composition and method for producing the material
申请人:——
公开号:US20040254258A1
公开(公告)日:2004-12-16
A cured matter obtained by polymerizing and curing a polymerizable composition comprising a compound having at least one episulfide in a molecule is reduced in an odor by adding a perfume to the polymerizable composition comprising the compound having at least one episulfide in a molecule.
A cloudiness of the lens is removed by raising a purity of sulfur to 98% or more.
A reduction in a chlorine content of the sulfur compound described above to 0.1% by weight or less elevates an oxidation resistance and a light fastness of the high refractive index optical material and improves a color tone thereof.
An optical product having a high refractive index and a high-degree transparency is provided by subjecting the composition in advance to deaerating treatment at 0 to 100° C. for one minute to 24 hours under a reduced pressure of 0.001 to 50 torr.