Synthesis of 1,4‐Dicarbonyl Compounds by Visible‐Light‐Mediated Cross‐Coupling Reactions of α‐Chlorocarbonyls and Enol Acetates
作者:Qiang Liu、Rui‐Guo Wang、Hong‐Jian Song、Yu‐Xiu Liu、Qing‐Min Wang
DOI:10.1002/adsc.202000791
日期:2020.10.21
visible‐light‐mediatedradical coupling reactions of α‐chloroketones and enol acetates to afford 1,4‐dicarbonyl compounds, which are important precursors and intermediates in organic synthesis. The reaction involves photoredox‐catalyzed activation of the α‐chloroketone upon photoelectron transfer, carbon–chlorine bond cleavage, and coupling of the resulting radical with the carbon–carbon double bond of the
The present invention provides an azolylacylquanidine compound of formula I
The present invention also provides methods for the use thereof to inhibit β-secretase (BACE) and treat β-amyloid deposits and neurofibrillary tangles.
enantioselective catalytic kinetic resolution of allylic alcohols through asymmetric isomerization with chiralBINOL derivatives-based alkoxides as bifunctional Brønsted base catalysts were described in the study. A number of chiralBINOL derivatives-based alkoxides were synthesized, and their structure-enantioselectivity correlation study in asymmetric isomerization identified a promising chiral Brønsted
Cross-coupling of dissimilar ketone enolates via enolonium species to afford non-symmetrical 1,4-diketones
作者:Keshaba N Parida、Gulab K Pathe、Shimon Maksymenko、Alex M Szpilman
DOI:10.3762/bjoc.14.84
日期:——
Due to their closely matched reactivity, the coupling of two dissimilar ketone enolates to form a 1,4-diketone remains a challenge in organic synthesis. We herein report that umpolung of a ketone trimethylsilyl enol ether (1 equiv) to form a discrete enolonium species, followed by addition of as little as 1.2-1.4 equivalents of a second trimethylsilyl enol ether, provides an attractive solution to
Potassium aryltrifluoroborates have proven to be useful reagents for the carbonylative aroylation of vinyl ketones; this study broadens the scope of potassium aryltrifluoroborates in homogeneous catalysis and shows that the solvent can act as the proton source for this family of reactions.