Amines molybdenum complexes

For a chiral molybdenum-based catalyst available in situ from commercial components, see (a) Aeilts SL, Cefalo DR, Bonitatebus PJ, Houser JH, Hoveyda AH, Schrock RR (2001) Angew Chem Int Ed 40 1452 (b) For the first enantiomerically pure solid-sup-ported Mo catalyst, see Hultzsch KC, Jernelius JA, Hoveyda AH, Schrock RR (2002) Angew Chem Int Ed 41 589 (c) For a chiral Mo catalyst, allowing RCM to small- and medium-ring cyclic amines, see Dolman SJ, Sattely ES, Hoveyda AH, Schrock RR (2002) J Am Chem Soc 124 6991 (d) For a novel adamantyl imido-molybdenum complex with advanced selectivity profiles, see Tsang WCP, Jernelius JA, Cortez GA, Weatherhead GS, Schrock RR, Hoveyda AH (2003) J Am Chem Soc 125 2591... 

Secondary amines can be added to certain nonactivated alkenes if palladium(II) complexes are used as catalysts The complexation lowers the electron density of the double bond, facilitating nucleophilic attack. Markovnikov orientation is observed and the addition is anti An intramolecular addition to an alkyne unit in the presence of a palladium compound, generated a tetrahydropyridine, and a related addition to an allene is known.Amines add to allenes in the presence of a catalytic amount of CuBr " or palladium compounds.Molybdenum complexes have also been used in the addition of aniline to alkenes. Reduction of nitro compounds in the presence of rhodium catalysts, in the presence of alkenes, CO and H2, leads to an amine unit adding to the alkene moiety. An intramolecular addition of an amine unit to an alkene to form a pyrrolidine was reported using a lanthanide reagent. 

Dimethyl-diaminobutane, cobalt(lU) hexa-amines, 35 130-131, 155-156 Dimethyldiazidosilane, preparation, 9 138 Dimethyldivinylsilane, molybdenum complex of, 4 83... 

Similarly, metathetical exchange of the labile acetonitrile ligands in the octahedral molybdenum complex (CO)2(MeCN)2BrMo( 3-C3Ph3) with a variety of bidentate amines led to the corresponding amino complexes (equation 267)311. These form crystalline acetonitrile solvates suitable for X-ray determination, which confirm the octahedral structure of these complexes and the occurrence of the cyclopropenyl and bromide groups in a tram-relationship. 

Table 5.15. Protective tribofilm formation from degradation of molybdenum dithiocarbamate (MoDTC), molybdenum dithiophosphate (MoDDP) and molybdenum amine-ester complex (MoAC) directly and in combination with ZDDPs or sulfur compounds...

Ammonium oxymolybdenum complexes with amines These complexes are prepared by the acid/base reaction of an acidic molybdenum source such as molybdenum trioxide, molybdic acid, ammonium molybdate [41] and ammonium thiomolybdates with oil-soluble amines [42], The preferred aminic compounds are lubricant additives known as dispersants, examples being succinimides and Mannich-type bases, as in Reactions (4.42) and (4.43) [41] ... 

The. V-alkylation of ephedrine is a convenient method for obtaining tertiary amines which are useful as catalysts, e.g., for enantioselective addition of zinc alkyls to carbonyl compounds (Section D. 1.3.1.4.), and as molybdenum complexes for enantioselective epoxidation of allylic alcohols (Section D.4.5.2.2.). As the lithium salts, they are used as chiral bases, and in the free form for the enantioselective protonation of enolates (Section D.2.I.). As auxiliaries, such tertiary amines were used for electrophilic amination (Section D.7.I.), and carbanionic reactions, e.g., Michael additions (Sections D. 1.5.2.1. and D.1.5.2.4.). For the introduction of simple jV-substituents (CH3, F.t, I-Pr, Pretc.), reductive amination of the corresponding carbonyl compounds with Raney nickel is the method of choice13. For /V-substituents containing further functional groups, e.g., 6 and 7, direct alkylations of ephedrine and pseudoephedrine have both been applied14,15. 

On the other hand, the oxidative deamination of amines in the coordination sphere of a molybdenum complex [162,163] requires water. Treatment of the complex, [(7r-C5Hs)2Mo(SMe2)Br] PFs with an excess of an amine, RR CHNH2 having hydrogen on the a-carbon (0-H) in water at 60 °C for several hours results in formation of the complex, [(ff-CsHs)2Mo(NH2CHRR )] PFj and the corresponding ketone or aldehyde RR CO, equation (121). 

The molybdenum neopentyUdene complex Mo(CHBu )(NR)(OBu )2 is the active catalyst used in a fascinating development for the synthesis of 11-Vt semiconductor clusters (ZnS, CdS, PbS) and silver and gold nanoclusters of predictable size within microdomains in films of block copolymers prepared by ROMP. Block copolymers of norbomene and a functionalized norbomene that wiU complex with a metal-containing compound were prepared and characterized as monodisperse materials. The functionalized component (amine, alkoxide, or thiolate) then sequestered the metal and the metallated block copolymer was cast into a film which was subsequently treated with H2S to convert the metal into the sulfide. The molybdenum complexes have also featured in the development of the synthesis of side-chain liquid crystal polymers by living ROMP.98 99... 

Carbonyl compounds are produced in the homogeneous oxidation of amines by complexed molybdenum salts. Disubstituted cyanamides react with hydroxylamine to give, depending on the reaction conditions, hydroxy-guanidines or amino-oxyformamidines. Triethylamine is quatemized by dichloromethane to afford chloromethyltriethylammonium chloride in a state of very high purity. ... 

An unusual binuclear molybdenum complex has been described, for which 2.27 is a possible structure. It undergoes metathetical bridge replacement, for example with sodium methoxide the tri-/<-methoxy analogue is prepared, and the halogen bridge can be split by amines giving 7i-C3H5Mo(CO)2(aniine)2Cl [88a]. 

Amines have also been exchanged by NHC, e.g., TMEDA can be replaced by two NHCs in [(tmeda)2VCl2], and pyridine by one NHC in complexes of chromium, molybdenum, and tungsten. ... 

In a three-component reaction, a cationic platinum isocyanide complex [(Ph3P)2Pt(CNR)Cl][BF4] is reacted with a /3-bromoamine and butyl lithium to give an imidazoldin-2-ylidene complex.This transformation can be a two-component reaction if the isocyanide ligand contains already the necessary amine functionality. This was shown for chromium, molybdenum, tungsten, and rhenium carbonyls. 

The complex [Fe"(bpca)2][Fe"(hfac)2]2, where Hbpca = bis(2-pyridylcarbonyl)amine, (230), consists of a pair of high-spin tris-/ -diketonate units bridged by a low-spin Ng entity." [Fe" (hfac)2] can bridge through the pyridyltriazine tptz, (231), to molybdenum(O), in Mo(CO)4( tptz), and rhenium(I) in ReCl(CO)3( tptz). ... 

The most active d metal peroxo complexes toward nucleophilic substrates, like amines, phosphines, thioethers, double bonds etc., are molybdenum, tungsten and rhenium derivatives vanadium and titanium catalysis is also important, in particular when... 

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