Relative thermodynamic stabilities of 2-(methoxymethylene)tetrahydrofuran and 5-methoxymethyl-2,3-dihydrofuran
作者:Esko Taskinen
DOI:10.1002/poc.610080103
日期:1995.1
The relative thermodynamic stabilities of the title compounds were determined by iodine catalyzed chemical equilibration in cyclohexane solution. The main point of interest was a determination of the thermodynamic stability of the OCCO moiety found in the exocyclic isomers, i.e. the stabilizing effect of a MeO group on the olefinic linkage of 2-methylenetetrahydrofuran. All three isomeric compounds
通过在环己烷溶液中碘催化的化学平衡来确定标题化合物的相对热力学稳定性。主要关注点是确定在环外异构体中发现的O C C O部分的热力学稳定性,即MeO基团对2-亚甲基四氢呋喃的烯烃键的稳定作用。所有三种异构体化合物的焓值基本相似,与以前的一些热力学数据相比,表明外型异构体中MeO基团的双键稳定能仅为约3 kJ mol -1。几何异构体之间的熵差可忽略不计,而内消旋异构体因ca 9 JK -1 mol -1的熵贡献而受到青睐。
Oxidative ring contraction of benzeneselenenate adducts of glycal ethers. synthesis of showdomycin analogues
作者:Andrew Kaye、Stephen Neidle、Colin B. Reese
DOI:10.1016/0040-4039(88)85267-5
日期:——
then with water and triethylamine gave () in 67% yield; the latter compound was treated with m-chloroperbenzoic acid and the putative ring-contracted aldehyde () obtained was converted into the showdomycinanalogue () in satisfactory overall yield. 3,4,6-Tri-O-benzyl--galactal () was similarly converted into the corresponding α--lyxoside ().
Reaction between glycal benzyl ethers and thallium(III) nitrate. Synthesis of showdomycin analogues.
作者:Andrew Kaye、Stephen Neidle、Colin B. Reese
DOI:10.1016/s0040-4039(00)82059-6
日期:1988.1
On treatment with thallium (III) nitrate, trihydrate in acetonitrile solution, 3,4,6-tri-O-benzyl-D-glugal () gives the ring-contracted aldehyde () which has been converted into the showdemycin analogue (); 2-(--2′-deoxyribofuranosyl)maleimide () has similarly been prepared from () in satisfactory overall yield.