Disclosed are a chiral multidentate ligand (I), a preparation, and an application thereof. In this method, compound (M1) is subjected to condensation with compound (M2) followed by amine deprotection in the presence of a deprotection reagent to obtain compound (M4). Compound (1) is subjected to deprotonation by butyl lithium and phosphorization followed by dimethylamino group substitution to produce compound (3). The compound (3) and the compound (M4) are reacted in the presence of triethylamine to produce chiral multidentate ligands.

##STR00001##

Process for the alkoxycarbonylation of trivinylcyclohexane.

A method of depolymerizing a biopolymer in a biomass is presented, the method comprising the step of contacting the biopolymer with a reaction system comprising at least one catalyst, at least one electron source, and at least one solvent. A second method of depolymerizing a biopolymer in a biomass is presented, the method comprising the step of contacting the biopolymer with an electrochemical cell comprising at least one catalyst, at least one solvent, at least one electrolyte, an anode, and a cathode. A third method of depolymerizing a biopolymer is presented, the method comprising the steps of providing a biopolymer; adding a photoredox-active functional group to the biopolymer to form a modified biopolymer; and irradiating the modified biopolymer with light in the presence of a reaction mixture; said mixture comprising a photoredox catalyst.

In one aspect, phosphine compounds comprising three adamantyl moieties (PAd.sub.3) and associated synthetic routes are described herein. Each adamantyl moiety may be the same or different. For example, each adamantyl moiety (Ad) attached to the phosphorus atom can be independently selected from the group consisting of adamantane, diamantane, triamantane and derivatives thereof. Transition metal complexes comprising PAd.sub.3 ligands are also provided for catalytic synthesis including catalytic cross-coupling reactions.

Provided is a metal complex as represented by formula I. The metal complex may be used as a catalyst for asymmetric catalytic hydrogenation, is capable of efficiently catalyzing and synthesizing a series of chiral p-aryl amides having high optical purity, and is especially capable of asymmetrically catalyzing and hydrogenating a tetra-substituted enamide compound, chiral amides having high optical purity are synthesized, and the carrying amount of ligand may reach 100,000.

##STR00001##

A mixture M includes at least one compound A selected from (a1) a compound of the general formula (I): R.sup.1R.sup.2R.sup.3Si—H, and/or (a2) a compound of the general formula (I′): (SiO.sub.4/2).sub.a(R.sup.xSiO.sub.3/2).sub.b(HSiO.sub.3/2).sub.b′(R.sup.x.sub.2SiO.sub.2/2).sub.c(R.sup.xHSiO.sub.2/2).sub.c′(H.sub.2SiO.sub.2/2).sub.c″(R.sup.x.sub.3SiO.sub.1/2).sub.d(HR.sup.x.sub.2SiO.sub.1/2).sub.d′(H.sub.2R.sup.xSiO.sub.1/2).sub.d″(H.sub.3SiO.sub.1/2).sub.d′″, and at least one compound B selected from (b1) a compound of the general formula (II): R.sup.4R.sup.5R.sup.6Si—O—R.sup.7, and/or (b2) a compound of the general formula (II′): R.sup.x.sub.3Si—O[—SiR.sup.x.sub.2—O].sub.m—[Si(OR.sup.7.sub.3)R.sup.x—O].sub.n—SiR.sup.x.sub.3, and at least one compound C selected from the cationic germanium(II) compound of the general formula (III): ([Ge(II)Cp].sup.+).sub.aX.sup.a−.

The alkylation of transition metal coordination catalyst complexes (such as metallocenes and/or post-metallocenes) in non-polar solvents with high conversion to the dialkylated transition metal coordination catalyst complex may be accomplished by reacting (a) a transition metal coordination catalyst complex comprising a transition metal linked to at least one an anionic donor ligand and at least one leaving group having a non-carbon atom directly linked to the transition metal, (b) an aluminum alkyl, and (c) a fluoride salt at 0° C. to 85° C. in a non-polar solvent to yield an alkylated transition metal coordination catalyst complex.

A process for the dehydrogenation of alkyl-containing compounds comprises reacting an alkyl-containing compound and a Group VI nitrosyl complex characterized as a transition metal complex having the composition Cp′M(NO)(R1)(R2), wherein Cp′ is selected from certain substituted and unsubstituted η.sup.5-cyclopentadienyl groups; M is W or Mo; and R1 and R2 are independently selected from CH.sub.2C(CH.sub.3).sub.3; CH.sub.2Si(CH.sub.3).sub.3; CH.sub.2(C.sub.6H.sub.5); CH.sub.3; hydrogen; and η.sup.3-allyl; provided that if R1 is hydrogen, R2 is η.sup.3-allyl; under conditions such that the alkyl-containing compound is converted to an olefin, and in particular embodiments, a terminal olefin. The dehydrogenation can be carried out using a neat and/or undried alkyl-containing compound and/or may be conducted under air, and does not require a sacrificial olefin to drive the reaction, thereby increasing convenience and decreasing cost in comparison with some other dehydrogenation processes.

The present invention discloses a homogeneous, single site catalyst of formula (I) and a process for preparation thereof using a ligand. The present invention further discloses a process for preparation of linear polyethylene of high molecular weight and degree of crystallinity by using the homogeneous, single site catalyst of formula I.

##STR00001##

The present invention relates to a process for the preparation of branched polyolefins having end-functionalized branches via the copolymerization of an olefin monomer and an olefin comprising main group metal hydrocarbyl chain transfer agent. The invention moreover relates to branched polyolefin having end-functionalized branches obtained by said process.