Al(OTf)3 exhibits superior catalyst performance in the Friedel–Crafts‐type benzylation using benzylicphosphate as an electrophile. The reaction can be conducted even with 0.2 mol‐% of the catalyst. Twenty‐one different diarylmethanes are formed. The chemoselective property of the catalyst toward the phosphate group over acetate and bromide is noteworthy.
Palladium-catalyzed indium-mediated reductive aromatic C−H allylation of N-benzylsulfonimides with allyl esters
作者:Xue-Ting Zhang、Shi-Kai Tian
DOI:10.1039/d3cc00881a
日期:——
electrophiles with allyl electrophiles has been established. A range of N-benzylsulfonimides smoothly participated in the palladium-catalyzed indium-mediated reductive aromatic C–H allylation with various allyl acetates, delivering structurally diverse allyl(hetero)arenes in moderate to excellent yields with good to excellent site selectivity. The use of inexpensive allylesters for the reductive aromatic
Alcohols 1a-g phosphorylation is performed in the Atherton-Todd reaction conditions (mixture of diethylphosphonate and carbone tetrachloride and triethylamine under ultrasonic irradiation). The expected phosphates 2a-g are obtained in good yields.
US7601849B1
申请人:——
公开号:US7601849B1
公开(公告)日:2009-10-13
Synthesis of Functionalized Diarylmethanes via a Copper-Catalyzed Cross-Coupling of Arylmagnesium Reagents with Benzylic Phosphates
作者:Christiane C. Kofink、Paul Knochel
DOI:10.1021/ol0616790
日期:2006.8.1
A combination of copper chloride, triethyl phosphite, and tetrabutylammonium iodide is a very efficient catalytic system for the synthesis of polyfunctionalized diarylmethanes, using the cross-coupling reaction of arylmagnesium halides with benzylic phosphates. The antibiotic Trimethoprim has been prepared using this Cu(I)-catalyzed cross-coupling in 52% overall yield (four steps).