The reaction of silyl enol ethers (la-le) with perfluoroalkyl iodides (2f-2k) initiated with sodium dithionite was studied, α-Perfluoroalkyl ketones (3) were synthesized in excellent yield by this method, α,β-Unsat...The reaction of silyl enol ethers (la-le) with perfluoroalkyl iodides (2f-2k) initiated with sodium dithionite was studied, α-Perfluoroalkyl ketones (3) were synthesized in excellent yield by this method, α,β-Unsaturated fluorinated ketones (4) were obtained easily by dehydrofluorination of the α-perfluoroalkyl ketones. A radical mechanism was proposed.展开更多
Per-and poly-fluoroalkylated α,β-unsaturated alkenals were synthesized by the reaction of silyl enol ether of alkanals with per-and poly-fluoroalkyl iodide initiated by Na_2S_2_O4 conveniently in high yield.Their co...Per-and poly-fluoroalkylated α,β-unsaturated alkenals were synthesized by the reaction of silyl enol ether of alkanals with per-and poly-fluoroalkyl iodide initiated by Na_2S_2_O4 conveniently in high yield.Their corresponding alkenol and 2,4-dinitrophenylhydrazone were also synthesized.展开更多
Benzoic acid and substituted benzoic acids are produced in photooxygenation of 1-aryl- 1-trimethylsilyloxy-1-propene(1)sensitized by 9,10-dicyanoanthracene(DCA)in acetonitrile.An electron transfer mechanism is propose...Benzoic acid and substituted benzoic acids are produced in photooxygenation of 1-aryl- 1-trimethylsilyloxy-1-propene(1)sensitized by 9,10-dicyanoanthracene(DCA)in acetonitrile.An electron transfer mechanism is proposed in which superoxide ion(O)combines with cation radical of 1 to form a dioxetane(2)which cleaves to form trimethylsilylbenzoate(3)and then 3 is converted to benzoic acids by hydrolysis.展开更多
Regioselective addition reactions of silyl enolates to a, b-unsaturated aldehyde and its acetal catalyzed by MgI2 etherate give aldol adducts (1, 2-addition) preferentially over Michael adducts (1, 4-addition). This ...Regioselective addition reactions of silyl enolates to a, b-unsaturated aldehyde and its acetal catalyzed by MgI2 etherate give aldol adducts (1, 2-addition) preferentially over Michael adducts (1, 4-addition). This unique regioselectivity is distinctly different with other Lewis acidic promoters and may be attributed to the high oxyphilicity of IMg+.展开更多
Several 14 alpha- and 14 beta -bromo baccatin III derivatives were synthesized by direct bromination and from silyl enol ether of 13-oxo-7-TES-baccatin III. 14 beta -Hyroxy baccatin III derivative was also obtained fr...Several 14 alpha- and 14 beta -bromo baccatin III derivatives were synthesized by direct bromination and from silyl enol ether of 13-oxo-7-TES-baccatin III. 14 beta -Hyroxy baccatin III derivative was also obtained from the same silyl enol ether.展开更多
文摘The reaction of silyl enol ethers (la-le) with perfluoroalkyl iodides (2f-2k) initiated with sodium dithionite was studied, α-Perfluoroalkyl ketones (3) were synthesized in excellent yield by this method, α,β-Unsaturated fluorinated ketones (4) were obtained easily by dehydrofluorination of the α-perfluoroalkyl ketones. A radical mechanism was proposed.
文摘Per-and poly-fluoroalkylated α,β-unsaturated alkenals were synthesized by the reaction of silyl enol ether of alkanals with per-and poly-fluoroalkyl iodide initiated by Na_2S_2_O4 conveniently in high yield.Their corresponding alkenol and 2,4-dinitrophenylhydrazone were also synthesized.
基金This work was supported by the National Natural Science Foundation of China.
文摘Benzoic acid and substituted benzoic acids are produced in photooxygenation of 1-aryl- 1-trimethylsilyloxy-1-propene(1)sensitized by 9,10-dicyanoanthracene(DCA)in acetonitrile.An electron transfer mechanism is proposed in which superoxide ion(O)combines with cation radical of 1 to form a dioxetane(2)which cleaves to form trimethylsilylbenzoate(3)and then 3 is converted to benzoic acids by hydrolysis.
基金We are grateful for the financial supports from the National Outstanding Youth Fund No.29925204)the Foundation for University Key Teacher by the Ministry of Education of Chinaa Visiting Fund of the National Laboratory of Applied Organic Chemistry.
文摘Regioselective addition reactions of silyl enolates to a, b-unsaturated aldehyde and its acetal catalyzed by MgI2 etherate give aldol adducts (1, 2-addition) preferentially over Michael adducts (1, 4-addition). This unique regioselectivity is distinctly different with other Lewis acidic promoters and may be attributed to the high oxyphilicity of IMg+.
文摘Several 14 alpha- and 14 beta -bromo baccatin III derivatives were synthesized by direct bromination and from silyl enol ether of 13-oxo-7-TES-baccatin III. 14 beta -Hyroxy baccatin III derivative was also obtained from the same silyl enol ether.
