Synthesis of a protected derivative of (2R,3R)-β-hydroxyaspartic acid suitable for Fmoc-based solid phase synthesis
作者:Boyaud France、Viguier Bruno、Inguimbert Nicolas
DOI:10.1016/j.tetlet.2012.10.120
日期:2013.1
Synthesis of d-threo-hydroxyaspartic acid, orthogonally protected and compatible with an Fmoc solid-phase peptidesynthesis strategy is reported. This synthetic procedure starting from (2R,3R)-dimethyltartrate is adaptable to a multi-gram scale. 2,2-Dimethyl-5-oxo-1,3-dioxazolane formation between the β-hydroxy alcohol and the β-carboxylic functions constitutes a key step of the differentiation of
Short intermolecular S...S contacts in a reaction product from the cyclic sulfate ester of dimethyl L-tartrate and 2-thioxo-1,3-dithiole-4,5-dithiolate.
作者:Turan Ozturk、David C. Povey、John D. Wallis
DOI:10.1016/s0040-4020(01)89422-9
日期:1994.1
Cyclicsulfate ester 6 reacts with dithiolate 4 to give dl cyclic products 8 and 9. The crystal of 9 shows two short S...S intermolecular interaction (<3.4 Å) between trithiocarbonate groups, due to cooperative polarisations and the highly asymmetric shape of the bonded S atom. The latter effect is mainly responsible for the ‘short’ S...S contacts in ET's radical cation salts. In contrast to similar
环状硫酸酯6发生反应与二硫醇4,得到DL环状产物8和9。9的晶体显示三硫代碳酸酯基团之间存在两个短的S ... S分子间相互作用(<3.4Å),这是由于合作极化和键合S原子的高度不对称形状所致。后一种效应主要是由于ET自由基阳离子盐中的“短” S ... S接触所致。与类似的系统相反,9中六元环的sp 3 C原子被置换到二硫醇平面的同一侧。
A Convenient Method for the Synthesis of Alkenes from <i>Vic</i>-diols <i>via</i> Cyclic Sulfates with Magnesium Iodide
作者:Doo Ok Jang、Yung Hyup Joo
DOI:10.1080/00032719808006486
日期:1998.3.1
Reaction of cyclic sulfates of vic-diols with magnesium iodide in acetonitrile produced the corresponding olefins in excellent isolated yields at room temperature. Cyclic sulfates of trans-diols gave trans-alkenes exclusively. Cyclic sulfates of cis-diols gave a mixture of cis- and trans-alkenes. However, the cyclic sulfate of cyclic cis-diol afforded the corresponding cis-alkene only.
A Facile Route to Olefins from<i>Vic</i>-Diols<i>Via</i>Cyclic Sulfates with Triphenylphosphine and Iodine
作者:Doo Ok Jang、Yung Hyup Joo、Dae Hyan Cho
DOI:10.1080/00397919708004099
日期:1997.7
Treatment of cyclic sulfates of vic-diols with triphenylphosphine and iodine offers the corresponding olefins in high yields at room temperature. Both cyclic sulfates of d,l-hydrobenzoin and meso-hydrobenzoin give trans-stilbene.
GAO, YUN;SHARPLESS, K. BARRY, J. AMER. CHEM. SOC., 110,(1988) N2, C. 7538-7539