Chlorination secondary amines

This reaction is reported to proceed at a rapid rate, with over 25% conversion in less than 0.001 s [3]. It can also proceed at very low temperatures, as in the middle of winter. Most primary substituted urea linkages, referred to as urea bonds, are more thermally stable than urethane bonds, by 20-30°C, but not in all cases. Polyamines based on aromatic amines are normally somewhat slower, especially if there are additional electron withdrawing moieties on the aromatic ring, such as chlorine or ester linkages [4]. Use of aliphatic isocyanates, such as methylene bis-4,4 -(cyclohexylisocyanate) (HnMDI), in place of MDI, has been shown to slow the gelation rate to about 60 s, with an amine chain extender present. Sterically hindered secondary amine-terminated polyols, in conjunction with certain aliphatic isocyanates, are reported to have slower gelation times, in some cases as long as 24 h [4]. 

Tlie bifunctional sulfenyl chloride 213 was obtained by chlorination of 144 in good yield, although excessive chlorination led to the saturated compound 214 (94CB533). A series of compounds 215-220 were obtained from 213 by reactions with secondary amines ferf-butyl methyl ketone hexane-2,4-dione 2,6-dimethylcyclohexanone diethyl malonate and acetylacetone, respectively. 

When reacted with dimethyl acetylenedicarboxylate, the amines produced ben-zotriazolylaminobutendioates 188 accompanied by A-benzotriazolyl substituted 2-pyridones only in the case of 5-amino-2-methyl-2//-benzotriazole, the triazolo-9,10-dihydrobenzo[d]azepine and an unusual cyclization product, triazolo-2-oxindole (convertible into 2-methyltriazolo[4,5-/]carbostyril-9-carboxylate) were formed. The quinolones 189 were aromatized to chloroesters 190 these in turn were hydrolyzed to chloroacids 191 and decarboxylated to 9-chlorotriazolo[4, 5-/]quinolines 192 (Scheme 58) (93H259). The chlorine atom could be replaced with 17 various secondary amines to give the corresponding 9-aminoalkyl(aryl) derivatives 193, some of which exhibit both cell selectivity and tumor growth inhibition activity at concentrations between 10 and 10 " M (95FA47). 

Condensation of normeperidine (81) with 3-chloropropan-l-ol affords the compound possessing the alcohol side chain (88). The hydroxyl is then converted to chlorine by means of thionyl chloride (89) displacement of the halogen by aniline yields pimino-dine (90). ° Condensation of the secondary amine, 81, with styrene oxide affords the alcohol, 91 removal of the benzyllic hydroxyl group by hydrogenolysis leads to pheneridlne (92). ... 

More than twenty years ago, Nesmeyanov s group showed that chlorine can be substituted by a variety of nucleophiles in FeCp(r 6-PhCl)+ [83, 84]. Indeed the chlorine substituent in the chlorobenzene (even) ligand is 1000 times more reactive than when it is located on the cyclopentadienyl (odd) ligand [85]. The FeCp+ is a good withdrawing group which is equivalent to two nitro groups in terms of activation. The reactions proceed under ambient conditions with primary or secondary amines and have been extended to other substituted chloroarene complexes [86, 87] Eq. (22), Table 2. 

Primary and secondary amines and amides are first chlorinated at nitrogen by the chlorine released by the gradually decomposing calcium hypochlorite. Excess chlorine gas is then selectively reduced in the TLC layer by gaseous formaldehyde. The reactive chloramines produced in the chromatogram zones then oxidize iodide to iodine, which reacts with the starch to yield an intense blue iodine-starch inclusion complex. 

Note This reagent sequence is a modiflcation of the reagent chlorine — potassium iodide — starch . Mobile phases containing ammonia must be removed completely before treatment with the reagent sequence, since otherwise the background will be colored too. Some secondary amines (e.g. diphenylamine) and some amides (e.g. 2,4-dinitrobenzamide) and methionine sulfoxide do not give reactions even in quantities of up to 1 to 2 (ig. 

By this method, different classes of PNs were prepared by replacing chlorine atoms of the polydichlorophosphazene intermediate by primary or secondary amines, alkoxide or aryl-oxide, or organ metallic reagents. " ... 

Titanium(IV) iodide is extremely hygroscopic. It dissolves in water with decomposition, and it fumes in air owing to hydrolysis. It forms 2 1 adducts with ammonia,7 pyridine,33 and ethyl acetate.34 With excess ammonia it undergoes ammo-nolysis to give ammonobasic titanium(IV) iodides.7 Analogous aminolysis reactions occur when titanium(IV) iodide is treated with an excess of primary or secondary amine.36 Titanium(IV) iodide is sparingly soluble in petroleum ether, moderately soluble in benzene, and even more soluble in chlorinated hydrocarbons and carbon disulfide. At elevated temperatures it... 

The three reactive chlorines on TsT have dramatically different reactivities toward nucleophiles in aqueous solution. The first chlorine is reactive toward hydroxyls as well as primary and secondary amine groups at 4°C and a pH of 9.0 (Abuchowski, 1977a Mumtaz and Bachhawat, 1991). Once the first chlorine is coupled, the second one requires at least room temperature conditions at the same pH to react efficiently. If two chlorines are conjugated to nucleophilic groups, the third is even more difficult to couple, requiring at least 80°C at alkaline... 

From phosphorus trichloride, benzyl alcohol and 2 mol. of a tertiary base, dibenzyl hydrogen phosphite (XIV), is obtained which on treatment with chlorine or a chlorinating agent (e.g. sulphuryl chloride)4 gives the phosphorochloridate (XV). Although not isolated, (XV) is almost certainly obtained by treatment of (XIV) with a polyhalogen hydrocarbon because reaction in the presence of an alcohol or of a primary or secondary amine gives a triester (XVI) or a phosphoramidate. 

Primary or secondary amines react with sodium or calcium hypochlorites to give TV-chloroamines, some of which are explosive when isolated. Application of other chlorinating agents to amines or their precursors may also produce the same result under appropriate conditions. 

The A -methyl derivative (32) was obtained from 31 via a Leuckart reaction and isolated as its hydrochloride 32 is also formed in the Hoffmann-Lbflfterreaction(photolysisinsulfuricacid)ofthei r-chloramine (33), since after separation of secondary amines and addition of methyl iodide a 10% yield of the methiodide (34) was obtained. The secondary amine (31) was also converted to its A-acyl and JV -nitroso derivatives (35-37) and (38), respectively, by conventional procedures. Free-radical chlorination of 37 gave the ca o-2-chloro derivative (39) and... 

Combination of the Hantzsch ester mediated transfer hydrogenation together with chlorine (116) or fluorine (117) electrophiles allows for the formal addition of HCl or HF aaoss a double bond in a catalytic asymmetric manner (Scheme 48) [178], Within this paper the reactions were further refined by the use of two cycle-specific secondary amines which effectively operated independently within the same reaction mixture. Impressively, this allowed access to either diastereoisomer of the product depending upon the absolute configuration of the catalyst used in the second step of the sequence. 

With these results available, it was not difficult to substitute the chlorine atom in compounds 91 with an additional equivalent of a primary or secondary amine in methanol [ 11,57] to obtain a, -diaminoesters 106 with different amino fragments (Scheme 35). 

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