Primary amine ligands

The C NMR spectra of the polysiloxane-immobilized primary amine ligand system before and after silylation of accessible silanols with hexame-thyldisilazane, given in Fig. 25.5, show very similar peak maxima positions for each of the three methylene carbons (Table 25.1), although there is apparently a small peak narrowing for C(2) and C(3) in the (CH3)3 Si-capped... 

Beller and coworkers found in 2009 that alkynes react with amines under the CO pressure (20 bar) in the presence of catalytic amounts of [Fe3(CO)i2] to the corresponding succinimide in moderate to excellent yields (Scheme 35) [110]. Various terminal and internal alkynes and ammonia or primary amines are adaptable for this transformation. Furthermore, [Fe(CO)s] as an iron source showed high activity. The catalytic activity, however, decreased considerably when a phosphine ligand such as PPh3 and ( Bu)2P("Bu) was employed. 

Oxidative carbonylation generates a number of important compounds and materials such as ureas, carbamates, 2-oxazolidinones, and aromatic polycarbonates. The [CuX(IPr)] complexes 38-X (X = Cl, Br, I) were tested as catalysts for the oxidative carbonylation of amino alcohols by Xia and co-workers [43]. Complex 38-1 is the first catalyst to selectively prepare ureas, carbamates, and 2-oxazolidinones without any additives. The important findings were the identity of the counterion and that the presence of the NHC ligand influenced the conversions. 2-Oxazohdinones were formed from primary amino alcohols in 86-96% yield. Complex 38-1 also catalysed the oxidative carbonylation of primary amines to ureas and carbamates. n-Propylamine, n-butylamine, and t-butylamine were transformed into the... 

Some other examples of metal-catalyzed substitutions are given in Scheme 11.10. Entries 1 to 3 are copper-catalyzed reactions. Entry 1 is an example of arylation of imidazole. Both dibenzylideneacetone and 1,10-phenanthroline were included as ligands and Cs2C03 was used as the base. Entry 2 is an example of amination by a primary amine. The ligand used in this case was (V,(V-diethyl sal icyl amide. These conditions proved effective for a variety of primary amines and aryl bromides with both ERG and EWG substituents. Entry 3 is an example of more classical conditions. The target structure is a phosphodiesterase inhibitor of a type used in treatment of asthma. Copper powder was used as the catalyst. 

Kaesz et al. have shown that simple, primary amines (e.g. MeNH2) will react with Ru3(CO)12 to form p-acetamido ligands at temperatures as low as -15°C. We find that simple primary, secondary and tertiary alkyl amines will react with Ru3(CO) 2 at temperatures of 70-150°C to undergo catalytic deuterium for hydrogen exchange reactions on the hydrocarbon groups and transalkylation (52). We have found that a... 

Ligands with S donors in addition to N and or O donors bound to Co11 are reasonably large in number. For example, the 4-amino-3-alkyl-l,2,4-triazole-5-thione can bind Co11 as a chelate employing the primary amine and thione substituents on the five-membered ring,510 whereas the trifluoromethyl ligand (afmt) forms [Co(afmt)2(H20)2](N03)2, defined as the A -irons isomer... 

Other coordination modes of trans-diammac have been identified where one (154) or both (155) primary amines are free from the metal.721 725 An extension of this concept involves attachment of active functional groups such as crown ethers selectively at one primary amine to generate ditopic ligands capable of electrochemically sensing alkali metal ions through their inductive effect on the Co11111 redox potential. One example is provided by (156) further, the 15-crown-5 and 18-crown-6 analogs were also prepared.726... 

A number of differently substituted A-(thiocarbamoyl)benzamidines (521) (R = Et, Bu NR2 = morpholino) have been complexed with Ni11. The ligands function in a bidentate manner, coordinating via the primary amine N and thione S atoms.1371... 

The QUINAP ligands are highly active for reaction of -substituted vinylarenes, thus, p-methoxystyrene gives the corresponding branched alcohol in 95% yield (57% ee) within 15 min at room temperature. Similarly, a combination of hydroboration/amination using (13) has allowed primary amines to be formed in a one-pot reaction of vinylarenes upon reaction of the B H addition product with MeMgCl/H2N0S03H (Scheme 10).5°... 

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