Related reagents

Immunoassays. Immunoassays (qv) maybe simply defined as analytical techniques that use antibodies or antibody-related reagents for selective deterrnination of sample components (94). These make up some of the most powerflil and widespread techniques used in clinical chemistry. The main advantages of immunoassays are high selectivity, low limits of detection, and adaptibiUty for use in detecting most compounds of clinical interest. Because of their high selectivity, immunoassays can often be used even for complex samples such as urine or blood, with Httle or no sample preparation. 

The Npys group can be. cleaved reductively with BU3P, H2O or mercaptoethanol. It is stable to CF3COOH (24 h), 4 M HCl/dioxane (24 h), and HF (1 h). The related reagent, 2-pyridinesulfenyl chloride, has also been proposed as a useful reagent for the deprotection of the 5-trityl, 5-diphenylmethyl, 5-acetamidomethyl, 5-/-butyl, and S-r-butylsulfenyl groups, but this reagent is very susceptible to hydrolysis. ... 

The reaction of enamines with ketene (146) and sulfene (147) are presumed to proceed by a two-step process involving an iminium intermediate such as 99. In fact, reaction with all electrophilic olefins such as acrylonitrile and related reagents could be thought of as going through an iminium intermediate similar to 99. Another example is given by addition to an enamine... 

Addition of Allylic Ylides and Related Reagents to Imines... 

Table 5 collects typical examples closely related reagents are often found in the indicated sections. 

After 12 hours at 4 kbar. this reaction provided only 35% of a 63 27 mixture of 22 and a compound which was tentatively assigned structure 23. It is assumed that 23 derives from epimerization of 21 prior to reaction with (aS,S,S)-5l0b. Whether this stereochemical assignment is correct or not, this result shows that 5 may have problems with configurationally labile aldehydes in demanding cases of mismatched double diastereosclcction. For further examples of double asymmetric induction with 5 or related reagents, see refs 31, 34 and 47. 

Note. The related reagent (diisopropoxymethylsilyl)methylmagnesium chloride (9) has been used similarly to hydroxymethylate organic halides and mesylates. 

Nucleophilic Attack at Halogen.- Further applications of tertiary phosphine-tetrahalogenomethane and related "reagents" have been described. The reactions of primary and secondary alcohols with potassium carboxylates in the presence of the triphenylphosphine-tetrachloromethane reagent lead to the formation of esters in good yield. However, application of this procedure... 

Alkenes can also be epoxidized directly with a variety of organic peroxy acids or related reagents such as peroxy carboximidic acid, RC(NH)OOH, which is readily available through an in situ reaction of... 

The stereochemistry of alcohol (and related reagents) addition to a silene is not known with certainty. The present authors have recently synthesized stable silenes where two geoisomers are possible (200) (also see Section VII). While NMR (1H, I3C, 29Si) data indicated the presence... 

Monodehydrohalogenation of allylic halides is another classical method for diene synthesis24. This method is complementary to double dehydrohalogenation as both the 1,2-dihalides and allylic halides are readily accessed from alkenes. The commonly employed protocol for diene synthesis, particularly for cyclic 1,3-dienes, is through the allylic monobromination of the alkene with A-bromosuccinimide or related reagents followed by dehydrobromination with hindered bases such as DBN or DBU (equation l)25. 

Substitution reactions on phosphorus-halogen compounds using organometallics and related reagents... 

Several methods for the preparation of the parent compound in this system, tris(trimethylsilyl)phosphite, have been reported.114 118 The application of this and related reagents in reaction with alkyl halides has been reported and used for the preparation of a variety of phosphonic acid analogues of phospholipids.114119-124 Interestingly, alkyl chlorides appear to be more reactive with the silyl reagents than do alkyl iodides, a reversal of the normally observed trend with alkyl esters of the phosphorus acids. (The particular use of silyl phosphorus reagents for the synthesis of biologically significant compounds has... 

Method A reaction of a 2-hydrazinopyrimidine with acid chloride or related reagent. Method B reaction of a hydrazone by oxidizing agent (e.g., bromine, ferric chloride). 

Table 5 Ring closures to [1,2,4]triazolo[3,4-b][1,3,4]thiadiazines by reaction of 3-mercapto-4-amino[1,2,4]triazoles with benzoin or related reagents ...

Dentritic phenylene-bridged Bi bismuthanes were obtained from Ph2BiCl and />-Li2C6H4 and related reagents.144... 

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