Nelson reagents

Kim, Y. K., and Sakano, Y. (1996). Analyses of reducing sugars on a thin-layer chromatographic plate with modified Somogyi and Nelson reagents, and with copper bicin-choninate. BioscL BiotechnoL, Biochem. 60 594-597. 

Gansauer, and a titanocene complex, TiCl3(THF)3, is also applicable as disclosed by Nelson and co-workers Catalytic pinacol coupling reactions occur with TiCU and zinc (or aluminum) in the presence of an acylating reagent such as acetic anhydride or acetyl chloride. ... 

T. D. Nelson, A.I. Meyers, Encyclopedia of Reagents for Organic Synthesis, John Wiley and Sons,... 

A number of authors have studied the reductive termination step. The classical work by Hermann and Nelson (121) showed that the reduction of the titanium in alkyltitanates occurred readily with the more alkylated species. The same authors (122) showed that the stability of the alkyl metal decreased markedly when the number of alkyls per metal atom increased. This is parallel to increased anionicity of the alkyl. Vanheerden (123) pointed out that the disproportionation of alkyl-titanium was bimolecular. Cotton (124) showed that the coupling occurs when phenyl Grignard reagents are mixed with various transition metal salts. This is through disproportionation or combination of the alkyl radicals. 

The Somogyi-Nelson assay (see Alternate Protocol 1) requires 30 min for the preparation of the low-alkalinity copper reagent and the same amount of time for the preparation of the arsenomolybdate reagent. An additional 24 hr should be considered for the 37°C incubation when preparing the arsenomolybdate reagent. Therefore, a total of 26 hr is necessary from the beginning of the experiments to obtaining the results. 

Pretreatment of contaminants with various reagents to produce degradates more amenable to microbial mineralization (Leeson et al, 1993) and treatment of soil slurries with microbial enzymes (Nelson and Jones, 1994) have been successful in remediation. 

In the reversible process, the redox reagents are turned over several times and recycled. The reversible mediators of oxidation can be a metallic redox couple, such as Ag+/Ag2+(Farmer et al. 1992), Co2+/Co3+(Leffrang et al. 1995), Ce3+/Ce4+(Nelson 2002), Fe2+/Fe3+(Dhooge and Park 1983), or inorganic ions such as Cr/CICT (Comninellis and Nerini 1995 Szpyrkowicz et al. 1995 (Panizza and Cerisola 2003a) or Br /BrO (Martinez-Huitle et al. 2005) added to or present in the electrolyte. The main drawback of the use of a solution redox couple is the need to subsequently separate the oxidation products from the mediator. 

Nelson s Color Reagent Dissolve 25.0 g of ammonium molybdate tetrahydrate in 300 mL of water. Carefully add... 

Add 2.00 mL of Nelson s Color Reagent to each tube, and mix thoroughly to dissolve any red precipitate that might be present. Let the solutions stand for 5 min. Add 2.0 mL of water to each tube, and mix. 

Nelson s A reagent—Dissolve 62.5 g of Na2C03 (anhydrous), 62.5 g of potassium sodium tartrate, 50 g NaHC03, and 500 g Na2S04 (anhydrous) in 1.75 liters of distilled water and dilute to 2.5 liters with distilled water. 

Reductions. Nelson et a/. selectively reduced enol acetates, vinyl chlorides, and x,/i-unsaturated aldehydes to the corresponding olefins. The reagent also reduces a-acetoxy ketones to the respective ketones. Ketones and esters arc not reduced. The... 

Nelson [31] reported that 2-alkylethynyl- or 2-arylethynyl tetrahydropyrans 49 treated, by Grignard reagents for 24 hr at room temperature in Et20, lead to high yields of S-,2 -coupled products 50 namely, the 5,6-allenic alcohols [Eq. (16)]. 

S84 Rupchock, P.A. and Nelson, C.D. (1984). A dry reagent ARIS immunoassay for the determination of lidocaine with the Ames Seralyzer reflectance photometer. Clin. Chem. 30, 1018, Abstr. 402. 

S158 Sommer, R., Nelson, C. and Greenquist, A. (1986). Dry-reagent strips for measuring phenytoin in serum. Clin. Chem. 32, 1770-1774. 

Nelson et al. used the oxidation of morphine to pseudomorphine 1n a post-column reactor. For the post-column derivatizing reagent, a solution of 50 mg potassium ferric cyanide in 250 ml of 4 M ammonia was used. Methanol - 0.1 M aqueous potassium bromide (12.5 87.5) was used as mobile phase for the separation of the alkaloids on a octadecyl stationary phase. The fluorescence was measured at 432 nm after excitation at 323 nm. 

Bernard, M., Ford, W.T., and Nelson, E.C., Syntheses of ethyl retinoate with polymer-supported Wittig reagents, J. Org. Chem., 48, 3164, 1983. 

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