Catalysts with a sheltered upbringing: Novel core–shell nanocomposite catalysts consisting of active metal nanoparticles encapsulated by macroligands have been prepared. They have Pd nanoparticles (PdNPs) as an active core and shell ligands having sulfoxide moieties coordinated to the PdNPs. The shell protects the catalyst from coordination by alkenes and allows the lead‐free selective semihydrogenation
Asymmetric synthesis via chiral acetal templates. 8. Reactions with organometallic reagents
作者:Stephen D. Lindell、John D. Elliott、William S. Johnson
DOI:10.1016/0040-4039(84)80037-4
日期:——
The titanium tetrachloride catalyzed coupling of organometallic reagents with chiralacetals 1 is shown to provide a convenient route for the preparation of a variety of chiral alcohols 4 of high optical purity.
已显示四氯化钛催化的有机金属试剂与手性缩醛1的偶联为制备各种高光学纯度的手性醇4提供了便利的途径。
Etudes sur les matières végétales volatiles. XLIV. Présence de nérolidol dans les huiles essentielles de papilionacées. (2ème communication)
作者:Y.-R. Naves
DOI:10.1002/hlca.19470300133
日期:1947.2.1
L'essence du bois rouge (vraisemblablement Myrospermum erythroxylon Fr. Allem.) possède une composition analogue à celle deshuilesessentielles de bois d'autres sophorées, elle est constitée en majeure partie de d-nérolidol.
A novel family of PNP ligands (W-Phos) was designed and applied in the copper-catalyzed asymmetric addition of linear Grignard reagents to ketones, allowing ready access to versatile chiral tertiary alcohols in high yields and with excellent enantioselectivities.
AbstractThree commercially available hydraulic/transmission lubricants based on rapeseed oil have been investigated for their lubricating properties. The coefficient of friction, scuffing‐load capacity, and pitting resistance were evaluated, and the results compared with a corresponding commercial mineral‐based oil.The results showed in general a substantially lower coefficient of friction and better pitting resistance for rapeseed‐based oils than for the mineral oil. Scuffing load capacity was, with one exception, the same for all oils. As a result of lower shear stresses during contact, and a higher viscosity index, the temperatures in the gearbox were lower for the rapeseed oils tested than for the mineral oil. Insufficient antiwear behaviour at high loads was found to be a major drawback of these vegetable oils.