Selective synthesis and stabilization of peroxides<i>via</i>phosphine oxides
作者:Fabian F. Arp、Shin Hye Ahn、Nattamai Bhuvanesh、Janet Blümel
DOI:10.1039/c9nj04858h
日期:——
ethane dioxide) with butanone and hydrogen peroxide. This peroxide is stabilized by forming strong hydrogen bonds to the phosphine oxide groups within an extended network, which has been characterized by single crystal X-ray diffraction. Reaction of acetylacetone with hydrogen peroxide, irrespective of the presence of phosphine oxide, leads to the stereoselective formation of two dioxolanes. Both cyclic
A process for preparing substituted biphenyls of the formula I
where R
1
=nitro or amino,
R
2
=cyano, halogen, C
1
-C
4
-haloalkyl, C
1
-C
4
-haloalkoxy or C
1
-C
4
-haloalkylthio,
n=from 0 to 3, and R
3
=hydrogen, cyano or halogen,
which comprises reacting a halobenzene of the formula II
in which Hal is chlorine or bromine,
in the presence of a base and of a palladium catalyst which consists of palladium and a bidentate phosphorus ligand of the formula III
where Ar is phenyl which is substituted if desired and R
4
and R
5
are each C
1
-C
8
-alkyl or C
3
-C
6
-cycloalkyl or together form a 2- to 7-membered bridge which may, if desired, bear a C
1
-C
6
-alkyl substituent,
in a solvent or diluent, with a phenylboronic acid IVa
a diphenylborinic acid IVb
or a mixture of IVa and IVb.
NEW ENTRY TO THE PREPARATION OF CHIRAL BIS(DICYCLOHEXYLPHOSPHINO)ALKANE DERIVATIVES. USE FOR RHODIUM-CATALYZED HYDROGENATION OF CARBONYL COMPOUNDS
作者:Keiji Yamamoto、Saeed-Ur-Rehman
DOI:10.1246/cl.1984.1603
日期:1984.9.5
of two representative chiral diphosphines, (−)-DIOP and (S,S)-Chiraphos, into the corresponding bis(dicyclohexylphosphino)alkane derivatives, the latter being used for chiral ligands of the rhodium(I) catalyst in the homogeneous hydrogenation of prochiral carbonylcompounds.
Metal-catalysed Poly(Ethylene) terephthalate and polyurethane degradations by glycolysis
作者:Raymundo Esquer、Juventino J. García
DOI:10.1016/j.jorganchem.2019.120972
日期:2019.12
The recovery of Polyol from PolyUretane (PU) and Bis(2-HydroxyEthyl) Terephthalate (BHET) fromPoly(Ethylene) Terephthalate (PET) from plastic waste by transesterification reactions was achieved, by using a wide scope of simple air-stable metal salts, Lewis acids, mixtures of commercially available phosphine/phosphite ligands with metal salts and low-valent [Ni(COD)2] as catalytic precursors, in the