Takeshi Kuri   Yoshihiko Mizukami   Mio Shimogaki   Morifumi Fujita   
Organic Letters 22(19) 7613-7616 2020年10月 [査読有り]
An oxetane intermediate during a direct aldol reaction was trapped with an internal aryl group to yield trans-tetraline products. The contribution of the oxetane intermediate was confirmed by 18O-isotope labeling experiments.
<p>The substitutions at the 2′- and/or 6′-positions of the quinoline ring of cinchonidine reduce both the intrinsic enantioselectivity and adsorption strength for the enantioselective hydrogenation of α-phenylcinnamic acid over Pd/C.</p>
M Fujita   M Furutani   T Okuyama   
TETRAHEDRON LETTERS 43(47) 8579-8581 2002年11月
The title reaction gives largely racemized 4-methylcycloheptanone, but the enantiomeric product in slight excess has a different form depending on the leaving group, ArI, of the iodonium salt. The results indicate that the photosolvolysis does not...
M Fujita   Y Sakanishi   M Nishii   T Okuyama   
JOURNAL OF ORGANIC CHEMISTRY 67(23) 8138-8146 2002年11月
Reactions of (R)-4-methyleyclohexylidenemethyl(phenyl)iodonium salt and its 3-trifluoromethylphenyl and 4-methoxyphenyl derivatives (1) with tetrabutylammonium mesylate and triflate were carried out in chloroform at 60 degreesC. The products inclu...
JOURNAL OF ORGANIC CHEMISTRY 67(23) 8130-8137 2002年11月
Optically active 4-methylcyclohexylidenemethyl(aryl)iodonium tetrafluoroborate (1.BF4-) was prepared and its solvolysis was carried out at 60 degreesC in various solvents. The main product is optically active 4-methylcycloheptanone (or its enol de...
M Fujita   Y Sakanishi   WH Kim   T Okuyama   
CHEMISTRY LETTERS 2002(9) 908-909 2002年9月
Cyclohexynes are effectively generated by treatment of cyclohex-1-enyliodonium salts with a mild base such as acetate and fluoride ion in chloroform. Regioselectivity of the nucleophilic addition of acetate ion to cyclohexynes depends on the 4-sub...
PROCEEDINGS OF THE JAPAN ACADEMY SERIES B-PHYSICAL AND BIOLOGICAL SCIENCES 78(7) 167-172 2002年9月
Molecular chirality of 4-methyleyclohexyhdenemethyl iodonium salt is used to probe the chirality of intermediate state of the reaction. A possible achiral intermediate, primary vinyl cation is excluded for the reactions of the iodonium salt under ...