Secondary amines/thiols

Autocatalysis may arise when the nucleophilic atom of the reagent is bound to a hydrogen atom which is eventually eliminated during the reaction. This occurs with neutral reagents such as primary or secondary amines, thiols, and alcohols. If the displaced group (usually an anion) is a sufficiently weak base, the proton is effectively transferred to any basic reactant. Hence, the best known examples of autocatalysis involve chloro-A-heteroaromatic compounds as the substrates. 

In general, EC reactions are typically observed according to the following general rank order (by relative ease of oxidation) o,p-quinol and o,p-aminophenol > tertiary amine > m-quinol rv phenol rv arylamine > secondary amine thiol > thioether primary amines, aliphatic alcohols. (HDVs) each redox active metabolite are obtained from the response across adjacent EC-Array sensors. These data are a reflection of the kinetic and thermodynamic components of electron transfer reactions. Since chemical structure is a critical determinant of an analyte s redox behavior, the intrinsic generation of an HDV with EC-Array provides qualitative information for each species. 

Pentavalent phosphorus compounds with a suitable leaving group, listed below, serve effectively as phosphorylating agents for some protic substrates such as alcohols, phenols, primary and secondary amines, thiols, phosphates, etc. 

Hydroxyls primary and secondary amines thiols Tertiary amines... 

Grosvenor, P., and Gray, D. O. (1990). 2,4-Dinotrophenylpyridium chloride, a novel and versatile reagent for the detection of amino acids, primary and secondary amines, thiols, thiolactones, and carboxylic acids during planar chromatography. J. Chromatogr. 504 456-463. 

Keywords Salicylic aldehydes, malononitrile, cyclic secondary amines/thiols, sodium formate, ethanol, room temperature, one-pot multicomponent reaction, tandem Knoevenagel-cyclocondensation, benzopyrano[2,3- f pyrimidmes/2-amino-4-arylsulfanyl-4//-chromene-3-corbonitriles... 

Most azolium ions are sufficiently reactive to be attacked by amines. Sometimes the initial adducts are stable ammonia and primary and secondary amines add to 1,3-dithiolylium salts at the 2-position to give compounds of the types NT3, RNT2 and R2NT, respectively, where T = the l,3-thiol-2-yl group (80AHC(27)l5l). 

RAFT polymerization can be performed simply by adding a chosen quantity of an appropriate RAFT agent to an otherwise conventional radical polymerization. Generally, the same monomers, initiators, solvents and temperatures are used. The only commonly encountered functionalities that appear incompatible with RAFT agents are primary and secondary amines and thiols. 

Chloro-4-nitrobenzo-2-oxa-l,3-diazole Mbd-Cl Primary and secondary amines, phenols and thiols 550,624... 

The reaction of the epoxide with a thiol group yields a thioether linkage, whereas reaction with a hydroxyl gives an ether and reaction with an amine results in a secondary amine bond. The relative reactivity of an epoxy group is thiol > amine > hydroxyl, and this is reflected by... 

The nucleophilic addition of alcohols [130, 204-207], phenols [130], carboxylates [208], ammonia [130, 209], primary and secondary amines [41, 130, 205, 210, 211] and thiols [211-213] was used very early to convert several acceptor-substituted allenes 155 to products of type 158 and 159 (Scheme 7.25, Nu = OR, OAr, 02CR, NH2, NHR, NRR and SR). While the addition of alcohols, phenols and thiols is generally carried out in the presence of an auxiliary base, the reaction of allenyl ketones to give vinyl ethers of type 159 (Nu = OMe) is successful also by irradiation in pure methanol [214], Using widely varying reaction conditions, the addition of hydrogen halides (Nu= Cl, Br, I) to the allenes 155 leads to reaction products of type 158 [130, 215-220], Therefore, this transformation was also classified as a nucleophilic addition. Finally, the nucleophiles hydride (such as lithium aluminum hydride-aluminum trichloride) [211] and azide [221] could also be added to allenic esters to yield products of type 159. 

The Mannich reaction of secondary amines R NH (dibenzylamine, piperidine, morpholine, etc.), aldehydes R2CHO (R2 = alkyl, Ph or 2-furyl) and thiols R3SH (R3 = alkyl, Ph or benzyl) results in a-amino sulphides, which react with Grignard compounds to give tertiary amines in good yields (equation 47)136. 

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