Catalyzed reactions, long chain

The essential feature of the chain reaction is the propagation step. In this step the intermediate is not consumed but acts simply as a catalyst for the conversion of material. Thus, each molecule of intermediate can catalyze a long chain of reactions, even thousands, before being finally destroyed. 

The reported quantum yields of the long-chain aldehydes in the luminescence reaction catalyzed by P. fischeri luciferase are 0.1 for dodecanal with the standard I (Lee, 1972) 0.13 for decanal with the standard I (McCapra and Hysert, 1973) and 0.15-0.16 for decanal, dodecanal and tetradecanal with the standard III (Shimomura et al., 1972). Thus, the quantum yield of long-chain aldehydes in the bacterial bioluminescence reaction appears to be in the range of 0.10-0.16. 

The a-oxoalkanephosphonic acids may also serve as starting materials for other interesting structures. They can be reacted with phenols catalyzed by Lewis acids adding two p-hydroxyphenyl groups [145]. This reaction may be of some interest by using long-chain alkyl phenols. 

Long-chain acyl-CoA esters are then converted to acylcamitine esters by readily reversible reactions with L-camitine catalyzed by carnitine palmitoyltransferase I (CPT I). 

Hydroaminomethylation of alkenes occurred to give both n- and /. so aliphatic amines catalyzed by [Rh(cod)Cl]2 and [Ir(cod)Cl]2 with TPPTS in aqueous NH3 with CO/H2 in an autoclave. The ratio of n-and /.soprimary amines ranged from 96 4 to 84 16.178 The catalytic hydroaminomethylation of long-chain alkenes with dimethylamine can be catalyzed by a water-soluble rhodium-phosphine complex, RhCl(CO) (Tppts)2 [TPPTS P(m-C6H4S03Na)3], in an aqueous-organic two-phase system in the presence of the cationic surfactant cetyltrimethy-lammonium bromide (CTAB) (Eq. 3.43). The addition of the cationic surfactant CTAB accelerated the reaction due to the micelle effect.179... 

Transition-metal- and enzyme-catalyzed alkylations of ammonia and amines with alcohols and diols have been reviewed59. RuCl2(PPh3)3 is a homogeneous catalyst for the reaction of long-chain terminal alcohols with secondary amines to give tertiary amines (equation 22)60. 

Modified cobalt complexes of the type frans-Co2(CO)6(phosphine)2 are promising candidates for certain transition metal-catalyzed reactions, in particular for the hydroformylation of long-chained olefins [117]. A series of complexes Co2(CO)6[P(alkyl) (aryl)m]2 (n 0,1,2,3 m S - n) was synthesized and used for solubility measurements. Since the basicity of phosphines affects the catalytic activity, use of fluorous substituents might induce unexpected changes in the activity. Therefore, also derivatives with an additional ethyl spacer between the fluorous group and the phosphine moiety were examined (Sect. 3.1). 

This enzyme [EC 2.3.1.76], also referred to as retinol fatty-acyltransferase, catalyzes the reaction of an acyl-CoA derivative with retinol to generate coenzyme A and the retinyl ester. The CoA derivative can be palmi-toyl-CoA or other long-chain fatty-acyl derivatives of coenzyme A. 

This enzyme [EC 2.5.1.26], also known as alkylglycerone-phosphate synthase, catalyzes the reaction of 1-acylglyc-erone 3-phosphate with a long-chain alcohol to produce 1-alkylglycerone 3-phosphate and a long-chain acid anion. In this reaction, the ester-hnked fatty acid of the substrate is removed and replaced with a long-chain alcohol in an ether hnkage. 

This enzyme [EC 6.2.1.15], also known as arachido-nateiCoA ligase, catalyzes the reaction of arachidonate with ATP and coenzyme A to generate arachidonyl-CoA, AMP, and pyrophosphate (or, diphosphate). The enzyme can also use 8,11,14-icosatrienoate as a substrate, but not the other long-chain fatty acids. It should be noted that this enzyme is not identical to long-chain acyl-CoA synthetase [EC 6.2.1.3]. 

This FMN-dependent enzyme [EC 1.1.3.15], also known as (5)-2-hydroxy-acid oxidase, catalyzes the reaction of a (5)-2-hydroxy acid with dioxygen to produce a 2-oxo acid and hydrogen peroxide. The enzyme exists as two major isoenzymes. The A form of the protein preferentially oxidizes short-chain aliphatic hydroxy acids. The B form preferentially oxidizes long-chain and aromatic hydroxy acids. The rat isoenzyme B form also acts as an L-amino-acid oxidase. 

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