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Ruthenium complexes tertiary amines

The three steps 32-34 have been suggested77 to be equilibria, and the overall equilibrium must lie far to the left because no adduct 23 is found in the reaction mixture when the reaction of sulfonyl chloride with olefin is carried out in the absence of a tertiary amine. A second possible mechanism involving oxidative addition of the arenesulfonyl halide to form a ruthenium(IV) complex and subsequent reductive elimination of the ruthenium complex hydrochloride, [HRulvCl], was considered to be much less likely. [Pg.1105]

To support the proposed hydride transfer as shown for the substrate geranylacetone 68 in Fig. 30 proline was linked to the primary face of P-CD yielding the tertiary amine 101 which was complexed with ruthenium and employed to ATH under standard conditions. No product was formed at all which is in good agreement with observations by other groups (31,49,50). The presence of a hydrogen... [Pg.55]

As in the case of ruthenium, a series of tra 5-dioxoosmium(VI) complexes with macrocyclic tertiary amine ligands, trans- 0 0)2(l )f (L=14-TMC, 15-TMC, 16-TMC, CRMes), have been synthesized by the method shown in Scheme 13. ... [Pg.776]

The electrochemical behavior of ruthenium(IV) 0x0 complexes of tertiary amines is similar to that of polypyridyls. For the [Ru (0)(L)(0H2)] /[Ru (L)(0H)(0H2)] couples, the ring size of the macrocycle L has little effect on E°. However, replacement of a tertiary amine nitrogen by a pyridyl nitrogen leads to an increase in F°. [Pg.825]

In 1989, a method for the peroxysilylation of alkenes nsing triethylsUane and oxygen was reported by Isayama and Mnkaiyama (eqnation 25). The reaction was catalyzed by several cobalt(II)-diketonato complexes. With the best catalyst Co(modp)2 [bis(l-morpholinocarbamoyl-4,4-dunethyl-l,3-pentanedionato)cobalt(n)] prodnct yields ranged between 75 and 99%. DiaUcyl peroxides can also be obtained starting from tertiary amines 87, amides 89 or lactams via selective oxidation in the a-position of the Af-fnnctional group with tert-butyl hydroperoxide in the presence of a ruthenium catalyst as presented by Murahashi and coworkers in 1988 ° (Scheme 38). With tertiary amines 87 as substrates the yields of the dialkyl peroxide products 88 ranged between 65 and 96%, while the amides 89 depicted in Scheme 38 are converted to the corresponding peroxides 90 in yields of 87% (R = Me) and 77% (R = Ph). [Pg.360]

Tertiary amines. Primary- amines bearing an a-hydrogen atom arc converted in high yield to symmetrical secondary amines when heated at 185° in the presence of about 0.2 mole % of this ruthenium complex (equation l).1 Use of larger amounts of... [Pg.141]

The results show that a number of ruthenium carbonyl complexes are effective for the catalytic carbonylation of secondary cyclic amines at mild conditions. Exclusive formation of N-formylamines occurs, and no isocyanates or coupling products such as ureas or oxamides have been detected. Noncyclic secondary and primary amines and pyridine (a tertiary amine) are not effectively carbonylated. There appears to be a general increase in the reactivity of the amines with increasing basicity (20) pyrrolidine (pKa at 25°C = 11.27 > piperidine (11.12) > hexa-methyleneimine (11.07) > morpholine (8.39). Brackman (13) has stressed the importance of high basicity and the stereochemistry of the amines showing high reactivity in copper-catalyzed systems. The latter factor manifests itself in the reluctance of the amines to occupy more than two coordination sites on the cupric ion. In some of the hydridocar-bonyl systems, low activity must also result in part from the low catalyst solubility (Table I). [Pg.183]

Selective oxidative demethylation of tertiary methyl amines is one of the specific and important functions of cytochrome P-450. Novel cytochrome P-450-type oxidation behavior with tertiary amines has been found in the catalytic systems of low-valent ruthenium complexes with peroxides. These systems exhibit specific reactivity toward oxidations of nitrogen compounds such as amines and amides, differing from that with RUO4. It was discovered in 1988 that low-valent ruthenium complex-catalyzed oxidation of tertiary methylamines 53 with f-BuOOH gives the corresponding a-(f-butyldioxy)alkylamines 54 efficiently (Eq. 3.70) [130]. The hemiaminal type 54 product has a similar structure to a-hydroxymethylamine intermediate derived from the oxidation with cytochrome P-450. [Pg.76]

Three types of product can be obtained from the reaction of amines with carbon monoxide, depending on the catalyst. (1) Both primary and secondary amines react with CO in the presence of various catalysts [e.g., Cu(CN)2, Me3N-H2Se, rhodium or ruthenium complexes] to give V-substituted and V,A-disubstituted formamides, respectively. Primary aromatic amines react with ammonium formate to give the formamide. Tertiary amines react with CO and a palladium catalyst to give an amide. (2) Symmetrically substituted ureas can be prepared by treatment of a primary amine (or ammonia) with CO " in the presence of selenium or... [Pg.850]


See other pages where Ruthenium complexes tertiary amines is mentioned: [Pg.178]    [Pg.820]    [Pg.343]    [Pg.582]    [Pg.735]    [Pg.735]    [Pg.772]    [Pg.784]    [Pg.786]    [Pg.823]    [Pg.82]    [Pg.119]    [Pg.143]    [Pg.266]    [Pg.26]    [Pg.360]    [Pg.178]    [Pg.240]    [Pg.64]    [Pg.4120]    [Pg.4124]    [Pg.59]    [Pg.246]    [Pg.178]    [Pg.560]    [Pg.126]    [Pg.547]    [Pg.203]    [Pg.175]    [Pg.164]    [Pg.4119]    [Pg.4123]    [Pg.1304]    [Pg.4758]    [Pg.242]   
See also in sourсe #XX -- [ Pg.4 , Pg.347 ]




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Ruthenium amine

Tertiary amine complexes

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