Preparation of (E)-4-Aryl-1,1,1-trifluoro-3-tosylbut-3-en-2-ones as Fluorinated Building Blocks and Their Application in Ready and Highly Stereoselective Routes to trans-2,3-Dihydrofurans Substituted with Trifluoromethyl and Sulfonyl Groups
作者:Haigang Yu、Jing Han、Jie Chen、Hongmei Deng、Min Shao、Hui Zhang、Weiguo Cao
DOI:10.1002/ejoc.201200180
日期:2012.6
(E)-4-Aryl-1,1,1-trifluoro-3-tosylbut-3-en-2-one fluorinatedbuildingblocks were prepared through a two-step process. Treatment of these (E)-4-aryl-1,1,1-trifluoro-3-tosylbut-3-en-2-ones with arsonium bromides in the presence of Cs2CO3 in CH2Cl2 at reflux resulted in highlystereoselective ring closure to provide 4-tosyl-5-trifluoromethyl-trans-2,3-dihydrofurans in good to excellent yields.
Synthesis, structure, and reactivity of (triphenylarsoranylidene)methylcyclohepta-2,4,6-trienone derivatives: reactions with heterocumulenes and an activated acetylene
作者:Yuhki Mitsumoto、Makoto. Nitta
DOI:10.1039/b205612g
日期:2002.10.7
Stable arsonium ylide derivatives 7a,b bearing cyclohepta-2,4,6-trienyl and electron-withdrawing CO2Et and CN groups, respectively, have been prepared for the first time through a reaction of 2-chlorocyclohepta-2,4,6-trienone with the corresponding arsonium methylide derivatives in the presence of ButOK. Compounds 7a,b are isolated as stable crystalline compounds, which do not undergo hydrolysis even
稳定的叶立德衍生物7a,b轴承环庚-2,4,6-三烯基和吸电子基团CO 2 Et和CN分别是通过与2-氯环庚-2,4,6-三烯酮在卜的存在相应的鉮甲基氧衍生物吨确定。化合物7a,b被分离为稳定的结晶化合物,不会经历水解即使在酸性条件下。X射线晶体分析表明,它们的As–O键距(7a为2.31Å,7b为2.39Å)低于范德华半径的总和(3.37Å),因此,砷和氧元素。为了构建一系列环庚环杂环并为了更好地理解一系列砷化钠,允许7a,b与二甲基碳杂杂环烯反应,异硫氰酸苯酯,二苯基碳二亚胺基和 异氰酸苯酯,在Wittig型反应中,随后进行电环化或正式的[8 + 2]型环加成消除 三苯ar硫醚 或者 氧化物 给 2 H-环庚[ b ]呋喃-2-硫酮, 它的 亚胺, 2-苯基亚氨基-2 H-环庚[ b ]吡咯, 和 2 H-环庚[ b ]呋喃-2-酮。另一方面,7a,b与乙炔二羧酸二甲酯 (DMAD)给
Réaction d'aldoses partiellement protégés avec des ylures d'arsenic stabilisés: synthèse de dérivés insaturés E acycliques et de dérivés C-glycosyle
Abstract The reaction of partially protected aldoses with (carbomethoxymethyl)triphenylarsonium bromide and zinc in toluene gave E α,β-unsaturated acyclic esters. When intramolecular transest erification occurred, bicyclic 1,4-lactone derivatives were formed concurrently. Otherwise, using these non alcaline conditions, olefination did not favour the formation of C -glycosyl derivatives. On the other
A highlystereoselectivesynthesis of exo-spiro[cyclopropane-1,4′-pyrazolin-5′-one] from 4-arylidene-3-methyl-1-phenyl-pyrazolin-5-one and arsonium bromide in the presence of base has been achieved. The triphenylarsine-catalyzed cyclopropanation of 4-arylidene-3-methyl-1-phenyl-pyrazolin-5-one with bromide in the presence of NaHCO3 has also been studied. Both exo and endo isomers were formed in this
在碱存在下,由4-亚芳基-3-甲基-1-苯基-吡唑啉-5-酮和溴化砷高度立体选择性地合成exo -spiro [cyclopropane-1,4'-pyrazolin-5'-one]实现了。在NaHCO 3存在下,还研究了三苯ar催化四溴化亚芳基-3-甲基-1-苯基-1-吡唑啉-5-酮的环丙烷化反应。两个外和内切形成在该反应中的异构体。产物的结构通过IR,MS,1 H NMR,元素分析和X射线衍射分析来表征。
A General Method for the Rapid High Yield Preparation of Pure Arsonium Salts. Preparation Of (3-Alkoxy-Carbonyl-2-Oxopropyl)Triphenylarsonium Bromides
作者:Cornelis M. Moorhoff
DOI:10.1080/00397919808004872
日期:1998.8
Abstract An easy, rapid method for the preparation of arsonium salts of high yield and purity, by heating an alkyl halide and triphenylarsine as a melt at about 80°C, is described.