Preparation of Various Carboxylic Acid Esters from Bulky Alcohols and Carboxylic Acids by a New Type Oxidation-reduction Condensation Using 2,6-Dimethyl-1,4-benzoquinone
A new-type oxidation-reduction condensation by using 2,6-dimethyl-1,4-benzoquinone (DMBQ), carboxylic acids and in situ formed alkoxydiphenylphosphines (1) including the bulky alkoxy group-substituted ones proceeded smoothly to afford the corresponding carboxylic acidesters in good to high yields. Alkoxydiphenylphosphines were formed in situ by treating either N,N-dimethylaminodiphenylphosphine (Ph2PNMe2)
Efficient Method for the Preparation of Carboxylic Acid Alkyl Esters or Alkyl Phenyl Ethers by a New-Type of Oxidation–Reduction Condensation Using 2,6-Dimethyl-1,4-benzoquinone and Alkoxydiphenylphosphines
A new-type of oxidation–reduction condensation proceeded smoothly to afford carboxylic acid alkyl esters or alkyl phenyl ethers in good to high yields by combined use of alkoxydiphenylphosphines (1...
一种新型氧化还原缩合反应顺利进行,通过结合使用烷氧基二苯基膦(1...
Efficient Methods for the Preparation of Alkyl−Aryl and Symmetrical or Unsymmetrical Dialkyl Ethers between Alcohols and Phenols or Two Alcohols by Oxidation−Reduction Condensation
作者:Taichi Shintou、Teruaki Mukaiyama
DOI:10.1021/ja0487877
日期:2004.6.1
generated in situ from chlorodiphenylphosphine (2) and alcohols, 2,6-dimethyl-1,4-benzoquinone (3), and phenols proceeds smoothly to afford alkyl-aryl ethers in good to high yields under neutral conditions. In a similar fashion, a new and efficient method for the preparation of symmetrical or unsymmetrical dialkyl ethers in good to high yields is established via tetrafluoro-1,4-benzoquinone (fluoranil) (4)
Photochemische Aren-Substitution in Cyclopentadienyleisen-Aren-Kationen—Eine allgemeine Synthese für Cyclopentadienyleisen-Bisphosphin-Ligand-Komplexe mit Liganden der 4. und 5. Hauptgruppe
作者:Hans Schumann、Liliana Eguren、Joseph W. Ziller
DOI:10.1016/0022-328x(91)83208-l
日期:1991.5
[C5H5Fe(1,4-(CH3)2C6H4)]PF6 undergoes photochemical p-xylene substitution in nitrile (RCN) solution in the presence of two equivalents of phosphorus donor ligands L upon UV-vis irradiation at λmax ⩾ 300 nm (R = CH3, C2H5, n-C3H7; L = P(OCH3)3 or 12[(C6H5)2PCH2]2). High yields of [C5H5Fe(L2)NCR]PF6 complexes are obtained. Thermal substitution of the coordinated nitrile ligand RCN in these complexes
[C 5 H 5 Fe(1,4-(CH 3)2 C 6 H 4)] PF 6在二当量的磷供体配体L存在下,经紫外光化学处理在腈(RCN)溶液中进行光化学对二甲苯取代可见辐射在λ最大⩾300纳米(R = CH 3,C 2 H ^ 5,NC 3 H ^ 7 ; L = P(OCH 3)3或12 [(C 6 H ^ 5)2 PCH 2 ] 2)。高产量的[C 5得到H 5 Fe(L 2)NCR] PF 6配合物。在第14和15族供体配体L'存在下,这些配合物中的配体腈配体RCN进行热取代可提供[C 5 H 5 Fe(L 2)L'] PF 6化合物的良好收率。讨论了这些配合物的选择反应。基于1 H,13 C和31 P NMR数据,并与相关的[C 5 H 5 Fe(CO)2 L'] X配合物进行比较,C 5 H 5 Fe +中心按以下顺序得出:L 2 = [(C 6 H 5)2 PCH 2 ] 2 >(P(OCH
Synthèse de phosphinites dérivés de sucres: Applications en cyclodimérisation du penta 2,4-diénoate de méthyle, en hydrogénation et en hydrosilylation de la pentolactone
Sugar-derived phosphinites, when used as ligands in the catalytic hydrogenation of α-ketopentolactone, lead to the corresponding alcohol with a better enantiomeric excess (20%) than in hydrosilylation (10%). In the cyclodimerisation of penta-2,4-dienoic acid methyl ester they lead to the meso cycloocta-3,7-diene-1,2-doic dimethyl ester.