herein an unprecedented highly efficient Guerbet‐type reaction at room temperature (catalytic TON up to >6000). This β‐alkylation of secondary methyl carbinols with primary alcohols has significant advantage of delivering higher‐order secondary alcohols in an economical, redox‐neutral fashion. In addition, the first enantioselective Guerbet reaction has also been achieved using a commercially available
Ligand-Controlled Regioselective Hydrocarboxylation of Styrenes with CO<sub>2</sub> by Combining Visible Light and Nickel Catalysis
作者:Qing-Yuan Meng、Shun Wang、Gregory S. Huff、Burkhard König
DOI:10.1021/jacs.7b13448
日期:2018.3.7
while employing 1,4-bis(diphenylphosphino)butane (dppb) as the ligand favors the formation of the anti-Markovnikov product. A range of functional groups and electron-poor, -neutral, as well as electron-rich styrene derivatives are tolerated by the reaction, providing the desired products in moderate to good yields. Preliminary mechanistic investigations indicate the generation of a nickel hydride (H-NiII)
Control of Transient Aluminum–Aminals for Masking and Unmasking Reactive Carbonyl Groups
作者:Francis J. Barrios、Brannon C. Springer、David A. Colby
DOI:10.1021/ol401265a
日期:2013.6.21
dimethylaluminum N,O-dimethylhydroxylamine complex, is effective at masking reactivecarbonylgroups in situ from nucleophilic addition. This reagent allows chemoselective addition of reducing reagents, Grignard reagents, organolithiums, Wittig reagents, and enolates into substrates with multiple carbonylgroups. Moreover, the trapped carbonylgroup, a stable aminal, can be unmasked in situ for additional synthetic
IMAGING ELEMENT CONTAINING A POLYMERIC BENZYLIC BLOCKED DEVELOPER
申请人:Eastman Kodak Company
公开号:US20040137380A1
公开(公告)日:2004-07-15
This invention relates to an imaging element comprising an imaging layer having associated therewith a compound of Structure I:
1
wherein PUG is a residue of removing a hydrogen from
2
wherein X, Y, and Z represent substituents selected independently from the groups hydrogen, alkyl group of 1 to 6 carbon atoms, cyclopropyl, aryl, arylalkyl, and heterocyclic groups, wherein at least one of X, Y, and Z is an aryl group and one of X, Y, Z, which may or may not be an aryl group, is attached in the direction of the backbone, and the other substituents are as defined in the specification. Such compounds have good reactivity and can by used to block photographically useful compounds such as developing agents until thermally activated under preselected conditions. Compounds according to the present invention are especially useful in color photothermographic imaging elements.
Imaging element containing a polymeric benzylic blocked developer
申请人:Eastman Kodak Company
公开号:US06770406B1
公开(公告)日:2004-08-03
This invention relates to an imaging element comprising an imaging layer having associated therewith a compound of Structure I:
wherein PUG is a residue of removing a hydrogen from
wherein X, Y, and Z represent substituents selected independently from the groups hydrogen, alkyl group of 1 to 6 carbon atoms, cyclopropyl, aryl, arylalkyl, and heterocyclic groups, wherein at least one of X, Y, and Z is an aryl group and one of X, Y, Z, which may or may not be an aryl group, is attached in the direction of the backbone, and the other substituents are as defined in the specification. Such compounds have good reactivity and can by used to block photographically useful compounds such as developing agents until thermally activated under preselected conditions. Compounds according to the present invention are especially useful in color photothermographic imaging elements.