摘要:
Processes for the preparation of nanopalladium (0) catalysts are disclosed. In some embodiments, the nanopalladium (0) catalysts may be reusable. In some embodiments, the nanopalladium (0) catalysts may be heterogeneous. Nanopalladium (0) catalysts may be employed for preparing coupling products by C—C bond formation through reaction of haloarenes in the presence of base. Haloarenes used in the coupling reaction may include chloroarenes that are typically unreactive. The use of heterogeneous nanopalladium catalyst may preclude the presence of trace amounts of palladium in the final coupling product.
摘要:
LDH-osmate of the formula [MII(1−x)MIIIx(OH)2][OsO42−]x/2.zH2O wherein MII is a divalent cation selected from the group consisting of Mg2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+ and Ca2+ and MIII is a trivalent ion selected from the group consisting of Al3+, Cr3+, Mn3+, Fe3+ and Co3+, and x is the mole fraction having integral value ranging from 0.2 to 0.33, and z is the number of water molecules and ranges from 1 to 4, useful as, a catalyst, and a process for the preparation thereof and use thereof to manufacture vicinal diols.
摘要:
The present invention provides a supported osmate useful as a reusable catalyst in the preparation of vicinal diols. The present invention also relates to a process for the preparation of supported osmates of the formula (S—NR3)2OsO4.nH2O wherein S is a support, R is an alkyl group, n is the number of water molecules and use thereof in the preparation of vicinal diols by asymmetric dihydroxylation (AD) of olefins in presence of cinchona alkaloid compounds.
摘要:
The present invention provides a supported osmate useful as a reusable catalyst in the preparation of vicinal diols. The present invention also relates to a process for the preparation of supported osmates of the formula (S—NR3)2OsO4.nH2O wherein S is a support, R is an alkyl group, n is the number of water molecules and use thereof in the preparation of vicinal diols by asymmetric dihydroxylation (AD) of olefins in presence of cinchona alkaloid compounds.
摘要:
The present invention relates to a multifunctional reusable catalyst and to a process for the preparation thereof on a single matrix of the support to perform multicomponent reaction in a single pot. The multifunctional catalysts of the invention are useful for the synthesis of chiral vicinal diols by tandem and/or simultaneous reactions involving Heck coupling, N-oxidation and AD reaction of olefins in presence of cinchona alkaloid compounds both as an native one and immobilized one in the said matrix support. This invention also relates to a process for preparing vicinal diols by asymmetric dihydroxylation of olefins in presence of cinchona alkaloid compounds employing reusable multifunctional catalysts as heterogeneous catalysts in place of soluble osmium catalysts.
摘要:
The present invention provides an ecofriendly method for preparing dinitramidic acid and its salts by nitration of ammonium sulfamate with fuming nitric acid as a nitrating agent using solid acid catalysts selected from the group consisting of a montmorillonite clay catalyst and metal ion exchanged K10 montmorillonite clay catalysts and surface supported catalysts and preparation of ammonium dinitramide by neutralization of the dinitramidic acid with ammonia and separation of ammonium dinitramide.
摘要:
The present invention provides a process for the preparation of amine oxide by reacting a tertiary or a secondary amine with hydrogen peroxide as an oxidant in the presence of a recyclable heterogeneous catalyst comprising a layered double hydroxide exchanged with an anion in the presence of an additive selected from the group consisting of benzonitrile, propionitrile, isobutyronitrile, benzamide and isobutyraride.
摘要:
An improved process for the preparation of acyl aromatic ethers useful as important intermediates for drugs and pharmaceuticals by reacting an aromatic ether with an acylating agent selected from a C2-C8 acid anhydrides, employing nano- and microcrystalline zeolite beta as catalyst is disclosed.
摘要:
The invention relates to a process for the preparation of high quality tetrabromobisphenol-A by reacting bisphenol-A with bromine and hydrogen peroxide as an oxidant in the presence of a heterogeneous catalyst in a biphase system consisting of water and water immiscible organic solvents.
摘要:
The invention concerns the use of a solid basic catalyst comprising a hydrotalcite structure wherein part at least of the compensating anions are fluoride anions F− for producing Knoevenagel of Michael condensation reactions. The invention also concerns novel solid basic catalysts comprising a hydrotalcite structure characterized by a Mg/Al molar ratio ranging between 2.5 and 3.8 wherein at least part of the compensating anions are fluoride anions F−, and methods for preparing said novel catalysts.