Activation of Mononuclear Arene Ruthenium Complexes for Catalytic Propargylation Directly with Propargyl Alcohols
作者:Emilio Bustelo、Pierre H. Dixneuf
DOI:10.1002/adsc.200600512
日期:2007.4.2
ligand. The in situ generated catalyst has been applied to catalytic transformations of alkynes and propargylic alcohols: propargylation of furans, propargyl ether synthesis from internal and terminal propargylic alcohols with propargyl, homopropargyl and allyl alcohols, selective dimerization of phenylacetylene into E-enyne, and propargyl alcohol rearrangement into α,β-unsaturated aldehydes and ketones
[(对伞花基)RuX(CO)(PR 3)] [OTf](R = Ph,Cy; X = Cl,OTf)类型的单核络合物促进呋喃与炔丙醇的直接催化炔丙基化。这些前体是通过活化炔丙醇从[(对-cymene)RuCl(OTf)(PR 3)]原位产生的,导致经由亚烯基和烯基-羟基卡宾中间体形成羰基配体。催化活性物质的产生需要短的初始热活化以诱导对-异丙基配体的去配位。在原位生成的催化剂已用于炔烃和炔丙醇的催化转化:呋喃的炔丙基化,内部和末端炔丙醇与炔丙基,高炔丙基和烯丙基醇的炔丙基醚合成,苯乙炔的选择性二聚为E-烯炔和炔丙醇重排为α ,β-不饱和醛和酮通过Meyer-Schuster重排。含有内部CC键的炔丙醇的炔丙基化表明通过Nicholas型中间体(金属稳定的炔丙基阳离子)的活化。
Metal-Free Catalytic Nucleophilic Substitution of Propargylic Alcohols
作者:Roberto Sanz、Alberto Martínez、Julia M. Álvarez-Gutiérrez、Félix Rodríguez
Direct scandium- and lanthanum-catalyzed etherifications of propargyl alcohols 1 and 6 in MeNO2–H2O provided propargyl ethers 3, 4 and 7 in high yields. In addition, reactions of 1 and 6 with thiols exclusively yielded the corresponding propargyl sulfides.
Rhenium-catalyzed Coupling of 2-Propynyl Alcohols and Several Nucleophiles via Dehydration
作者:Yoichiro Kuninobu、Hirokazu Ueda、Kazuhiko Takai
DOI:10.1246/cl.2008.878
日期:2008.8.5
Treatment of 2-propynyl alcohols with several nucleophiles in the presence of a catalytic amount of a rhenium complex, [ReBr(CO)3(thf)]2, gave coupling products via dehydration. In these reactions, C–C, C–O, and C–S bonds can be constructed under mild conditions.