Reactions of pent-4-en-2-yl carboxylates and their derivatives with iodosylbenzene gave 2,4-disubstituted and 2,3,5-trisubstituted tetrahydrofurans with high diastereomeric ratio. The tetrahydrofuranylation may proceed via a 1,3-dioxan-2-yl cation...
Optically active methyl 2-[2-(diacetoxyiodo)phenoxy]propanoate and its derivative were prepared and used for oxygenation of but-3-enyl carboxylates leading to tetrahydrofuran-3-yl carboxylates as an enantiomerically enriched form. (c) 2007 Elsevie...
JOURNAL OF PHYSICAL ORGANIC CHEMISTRY 20(4) 241-244 2007年4月 [査読有り]
Solvolyses of monomethoxy-and dimethoxyphenyl(phenyl)iodonium (ArI(+)Ph) tetrafluoroborates were carried out in methanol and 2,2,2-trifluoroethanol (TFE) at 130 degrees C. The solvolysis products include alkoxide substitution products (ArOR and Ph...
RECENT DEVELOPMENTS IN CARBOCATION AND ONIUM ION CHEMISTRY 965 68-87 2007年 [査読有り]
General reactivities of vinyl iodonium salts are summarized, and reactions of cyclohexenyl, 1-alkenyl, styryl, and 2,2-disubstituted vinyl iodonium salts are discussed in relation to possible formation of vinyl cation intermediates. Primary vinyl ...
Morifumi Fujita   Hee Jin Lee   Takashi Sugimura   Tadashi Okuyama   
CHEMICAL COMMUNICATIONS (11) 1139-1141 2007年 [査読有り]
Reaction of 4-acyloxybut-1-enylsilanes with iodosylbenzene in the presence of BF3 center dot OEt2 gave 4-acyloxy-2-oxobutylsilane and 3-acyloxytetrahydrofuran-2-ylsilane via a 1,3-dioxan-2-yl cation intermediate, which is generated by participatio...
The ring opening of alkylidenecyclopropanone acetal under acidic conditions produces the 1-alkylidene-2-oxyallyl cation as an intermediate, which reacts with furan to give the [3+2] and [4+3] cycloadducts as well as an electrophilic substitution p...
The ring opening of alkylidenecyclopropanone acetal under acidic conditions produces the 1-alkylidene-2-oxyallyl cation as an intermediate, which reacts with furan to give the [3+2] and [4+3] cycloadducts as well as an electrophilic substitution p...
M Fujita   S Hanagiri   T Okuyama   
TETRAHEDRON LETTERS 47(25) 4145-4148 2006年6月
Ring opening reactions of 2-cyclohexylidene-3,3-dimethylcyclopropanone acetal (1) are readily induced by treatment of hydrogen chloride in various solvents. Bond cleavage takes place at the C1-C2 or C2-C3 bond, and the ratio of C1-C2/C2-C3 cleavag...
M Fujita   S Hanagiri   T Okuyama   
TETRAHEDRON LETTERS 47(25) 4145-4148 2006年6月
Ring opening reactions of 2-cyclohexylidene-3,3-dimethylcyclopropanone acetal (1) are readily induced by treatment of hydrogen chloride in various solvents. Bond cleavage takes place at the C1-C2 or C2-C3 bond, and the ratio of C1-C2/C2-C3 cleavag...