Ligand Control of <i>E</i>/<i>Z</i> Selectivity in Nickel-Catalyzed Transfer Hydrogenative Alkyne Semireduction
作者:Edward Richmond、Joseph Moran
DOI:10.1021/acs.joc.5b01047
日期:2015.7.2
A nickel-catalyzed transfer hydrogenative alkynesemireduction protocol that can be applied to both internal and terminal alkynes using formic acid and Zn as the terminal reductants has been developed. In the case of internal alkynes, the (E)- or (Z)-olefin isomer can be accessed selectivelyunder the same reaction conditions by judicious inclusion of a triphos ligand.
solvents; however, the rate of reaction was significantly faster in the presence of water. Thermal stability evaluation of the postreaction mixtures in DMSO and 3:1 DMSO/water by differential scanning calorimetry indicated that the onset temperatures of thermaldecomposition were significantly lower than that of neat DMSO. Evaluation of the substrate scope revealed that the substitution pattern on the bromobenzene
Rhodium-catalyzed oxidative decarbonylative Heck-type coupling of aromatic aldehydes with terminal alkenes
作者:Lei Kang、Feng Zhang、Lin-Ting Ding、Luo Yang
DOI:10.1039/c5ra21610a
日期:——
rhodium-catalyzed oxidative decarbonylative Heck-type coupling of aromatic aldehydes with terminal alkenes to afford 1,2-disubstituted alkenes with good regio- and E-selectivity is developed. This reaction employs readily available aromatic aldehydes as the aryl electrophile counterpart and relies on selected acyl chloride as the crucial additive to activate the rhodium catalyst precursor.
A series of 3-styrylbenzimidamides were synthesized and biologically evaluated in a cell free FRET assay as
potential BACE1 inhibitors. Some of the synthesized analogues were discovered to have moderate BACE1 inhibitory activities
with IC50 values ranging from 9.3 to 295.8 μM. Molecular docking study proposed that the most potent compound
(E)-2d bound to BACE1 differently in S3-S2’ subpockets forming no polar interaction with the catalytic Asp dyad compared
with the 3-styrylbenzimidamides. The results would contribute to the further optimizations on benzimidamide scaffold
to achieve novel small molecular BACE1 inhibitors with improved potencies.