Amines reagents and

Mercaptans and hydrogen sulfide were determined using Tappers (50) modifications of the methods of Sliwinski and Doty (47) and Marback and Doty (38). A 0.1 M amine solution was used for the mercaptan analysis since it was found to give as much color development in the concentration range used as the specified 0.5M amine reagent and a much lower reagent blank reading. 

Formation of imidazolines 315a,b namely with cyclohexylamine and isopropylamine can be explained by the comparative ease of their oxidation and the relative stability of the corresponding ketimines. Similar heterocyclizations have been shown to proceed with other combinations of 3-alkylamino-6,8-dimethylpyrimido[4,5-c] pyridazine-5,7(6//,8//)-diones 311 and primary alkylamines. Their directionality is determined by the relative ease of oxidation of the amine reagent and the substrate amino group. Two general possibilities leading to isomeric imidazolines exist... 

The monocyclic diazines, triazines, and tetrazines are all theoretically subject to electrophilic attack at one or more of their annular nitrogen atoms by protons alkylating, acylating, and aminating reagents and peracids. Coordination with metals could also be classified under this heading. 

Scheme 2.52 The most usual fluorinated amine reagents and their syntheses. Top the per-fluoropropene-based reagent exists as an equilibrium mixture of an , -difluoroalkylamine and the two isomeric a-fluoroenamines. Middle The dimethyl(2-chloro-l,2-difluorovinyl)amine reagent has a more defined composition. Bottom Synthesis of an a-fluoroenamine fluorination reagent [120—122].

Electrophilic Amination. r-Butyl )V-lithio-)V-(/)-toluenesulfonyloxy)carbamate (1) is prepared from Abutyl W(/)-toluenesulfonyloxy)carbamate, which is easily obtained on a large scale by tosylation of the commercially available f-butyl )V-hydroxycarbamate. (1) is an electrophilic aminating reagent and a synthetic equivalent of +NHBoc . It reacts with alkyllithium reagents (eq 1) or arylcopper reagents (eq 2) to provide primary amines in their (V-Boc protected form. 

NFSi has been used as a versatile oxidant in reactions that involve a Pd(II)/Pd(IV) catalytic cycle. The oxidative addition of NFSi to Pd(II), which generates a reactive Pd(IV) species is the first step in the functionalization of a Pd-C bond as exam-plified in the arylation of a Pd(II)-alkyl complex (eq 56). Depending on the reaction conditions, a competition between di-amination (see section NFSi as an amination reagent) and car-boamination exists. In the presence of an alcohol as solvent, a palladium-catalyzed alkoxyamination is observed with use of NFSi as oxidant. ... 

Dissolve equivalent quantities of the reagent and of the amine in a small amount of rectified spirit. K no reaction appears to take place in the cold, reflux the mixture for 5-15 minutes. Upon cooling (and scratching with a glass rod, if necessary) the crystaUiiie thiourea separates. RecrystaUise it from rectified spirit or from 60-b0 per cent, alcohol. 

Rearrangement of the diazo ketone, with loss of nitrogen, in the presence of suitable reagents and a catalyst (colloidal silver, silver oxide, or silver nitrate in the presence of ammonia solution). An acid is formed In the presence of water, an amide results when ammonia or an amine is used, and an ester is produced in the presence of an alcohol ... 

The thiazolyl radicals are, in comparison to the phenyl radical, electrophilic as shown by isomer ratios obtained in reaction with different aromatic and heteroaromatic compounds. Sources of thiazolyl radicals are few the corresponding peroxide and 2-thiazolylhydrazine (202, 209, 210) (see Table III-34) are convenient reagents, and it is the reaction of an alky] nitrite (jsoamyl) on the corresponding (2-, 4-, or 5-) amine that is most commonly used to produce thiazolyl radicals (203-206). The yields of substituted thiazole are around 40%. These results are summarized in Tables III-35 and IIT36. 

This Michael-type addition is catalyzed by lanthanum(3+) [16096-89-2] (80). Ethylene glycol [107-21-1] reacts with maleate under similar conditions (81). A wide range of nucleophilic reagents add to the maleate and fumarate frameworks including alcohols, ammonia, amines, sulfinic acids, thioureas, Grignard reagents, Michael reagents, and alkali cyanides (25). 

Phosphorus(V) sulfide reacts with olefins, amines, Grignard reagents, and terpenes (6,26) as follows ... 

The halogen influences the rate of reaction, and, in general, the order of reactivity is HI > HBi > HCl. Impoitant uses of etfiyl chloiide include the manufacture of tetraethyllead and ethylceUulose. Ethyl bromide can be used to produce ethyl Grignard reagent and various ethyl amines. 

The decomposition of (536) with hydrogen sulfide yields pyrazole (76T1909). The 1-phosphorylpyrazoles (537) are suitable reagents for the phosphorylation of alcohols, amines, hydrazines and azides (76AG(E)378). 

Diaziridines (151) are formed from a carbonyl compound, an amine and an electrophilic aminating reagent (B-67MI50800, 79AHC(24)63>. 

In the presence of aprotonic organic solvents, both aromatic and aliphatic amines interact with 4-nitrophenyldiazonium in the same way. The first stage yields fast in corresponding triazenes. At the second stage, irrespective of initial amine nature, triazenes interact with an excess of diazo reagent and fonu l,3-bis(4-nitrophenyl)-triazene. Triazenes of aliphatic amines transform fast as well. In case of aromatic amines, the second stage yield depends on the inductive constants of substituents in an azo component. 

In recent years the solid-phase hydrosilylation reaction was successfully employed for synthesis of hydrolytically stable surface chemical compounds with Si-C bonds. Of special interest is application of this method for attachment of functional olefins, in particular of acrolein and some chiral ligands. Such matrices can be used for subsequent immobilization of a wide range of amine-containing organic reagents and in chiral chromatography. 

Trimethylsilyl cyanide. This reagent readily silylates alcohols, phenols, and carboxylic acids, and more slowly, thiols and amines. Amides and related compounds do not react with this reagent. The reagent has the advantage that a volatile gas (HCN is highly toxic) is the only byproduct. 

Dimethylfarmamlde and triethyl amine were purchased from Baker (Baker Analyzed Reagent) and used without further purification. 

Aryl isothiocyanates can be prepared by the action of thio-phosgene on the arylamine (this reaction fails with naphthyl compounds), by fission of a 5ym-diaryIthiourea with acidic reagents (this reaction involves the loss of half the amine used), and by the decomposition of an ammonium aryldithiocar-bamate (low yields are reported for naphthyl and other compounds).The procedure described here is that of Baxter, Cymerman-Craig, Moyle, and White. ... 

Lithium aluminum hydride (LiAlH4) is the most powerful of the hydride reagents. It reduces acid chlorides, esters, lactones, acids, anhydrides, aldehydes, ketones and epoxides to alcohols amides, nitriles, imines and oximes to amines primary and secondary alkyl halides and toluenesulfonates to... 

Similarly, Itexafluoroprapylene undergoes fluoride ion induced homotelo-merization to give a series of dimers and trimers These telomerizations can be induced by other nucleophiles, such as amines Indeed, the selectivity of the pi oce-,s can be changed significantly by varying reagents and reaction conditions [25, 26] (equations 19 and 20)... 

The reaction of a cepham primary amine with 20 eq. of 37% formalin produces the dioxazine in 75% yield. The dioxazine is sufficiently stable to allow the formation of Wittig reagents and to carry out an olefination with formaldehyde. Treatment of the dioxazine with 6 N HCl in CH2CI2 releases the amine in excellent yield. ... 

Reactions with uncharged species such as amines, alcohols, and water offer frequent opportunities for investigations under pseudo-first-order conditions since many of these reagents are suitable solvents. However, the reactions with amines have often been investigated in alcohols and in non-hydroxylic solvents 27-29a have been found to follow second-order kinetics. 

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