Unexpected transformation of methyl 3,6-anhydro-2,7-dideoxy-7-iodo-4,5-O-isopropylidene-D-allo-heptonate in the dehydroiodination reaction with 1,8-diazabicyclo[5.4.0]undec-7-ene
Unexpected transformation of methyl 3,6-anhydro-2,7-dideoxy-7-iodo-4,5-O-isopropylidene-D-allo-heptonate in the dehydroiodination reaction with 1,8-diazabicyclo[5.4.0]undec-7-ene
Ultrasound-accelerated synthesis of chiral allylic alcohols promoted by indium metal
作者:J.S Yadav、B.V.S Reddy、K Srinivasa Reddy
DOI:10.1016/s0040-4020(03)00736-1
日期:2003.7
The 2-iodomethyl-O-isopropylidine acetals undergo smoothly β-elimination by indium metal in methanol under sonication to afford the corresponding allylic alcohols in excellent yields with high selectivity. This method tolerates both acid and base labile functional and protecting groups and also free hydroxyl groups present in the molecule. Improved yields and enhanced rates are the remarkable features
Uncommon transformations of methyl (1S,2S,3R,4R)-2,3-isopropylidenedioxy-5-iodomethyl-2-tetrahydrofurylacetate initiated by bases
作者:N. A. Ivanova、Z. R. Valiullina、O. V. Shitikova、M. S. Miftakhov
DOI:10.1134/s1070428006110169
日期:2006.11
Methyl (I S,2S,3R,4R)-2,3-isopropylidenedioxy-5-iodomethyl-2-tetrahydrofurylacetate prepared in two stages from D-ribose acetonide underwent a series of uncommon transformations under the treatment with bases providing the following different products depending on the base applied: methyl 3-(5-acetyl-2,2-dimethyl- 1,3-dioxol-4-yl)propionate (DBU), methyl 2,3-isopropybdenedioxy-7-oxabicyclo[2.2.1]heptane-6-carboxylate (t-BuOK), methyl (5R)-2,2-dimethyl-5-[(2R)-oxiranyl]-1,3-dioxolan-4-ylidene}propionate and methyl-(E)-3-(4S,5R)-2,2-dimethyl-5-[(IR)-(2-oxiranyl)]-1,3-dioxolan-4-yl}-2-propenoate (t-BuOK and LDA).