Reactions with secondary amines

Reaction with secondary amines (Sec tion 17 11) Isolated product IS an en amine Carbinolamine intermediate can not dehydrate to a stable imine... 

Amino derivatives are obtained by standard reactions with secondary amines, lithium amides or... 

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. 

BMIM]BF4 and [BMIMJPFg were used as catalysts to activate aryl halides for nucleophilic substitution reactions with secondary amines at room temperature. The corresponding arylamines were obtained in high yields (159). 

Nucleophilic attack at N(3) takes place in the benzofuroxan series. For example, the reaction with secondary amines leads to o-nitroarylhydrazines (Scheme 34) (88JCS(P1)145). 

Aminoisocoumarins are also available from the isochromandione through initial reaction with secondary amines to give homophthalamic acids (498) (78JCS(Pl)1338). Cyclization in acetic anhydride and perchloric acid gives the homophthalisoimidium perchlorates (499)... 

Certain geminal difluoro groups arc easily aminolyzed yielding imines or enamines.3,20-24 An imine-enamine equilibrium is generally observed,13,25 - 28 which is dependent on the substrate and the amine used. Nevertheless, /i-imino carboxylic esters are predominantly obtained when a-hydrylperfluoro esters (e. g., 4) are reacted with primary amines, while reaction with secondary amines leads to the respective enamines.29,30... 

The trans-phenanthrene-9,10-amino alcohols (261) are formed from 1 and its derivatives by reaction with secondary amines.154... 

For benzo[c]pyrylium salts having different alkyl substituents in positions a(l) and a (3), the reaction with secondary amines loses its predictable regioselectivity. Thus, reaction with dimethylamine, independent of the solvent, gives rise to /3-naphthylamine 185, from l-ethyl-3-methyl-substituted salt 183 (81KGS1608), and a-naphthylamine 186 from 1-benzyl derivative 184 (88UP1). In the former case, the nucleophilic attack occurs in position 3, whereas in the latter case, it takes place in position 1. 

Similar to the reaction of 2-benzopyrylium salts with ammonia (Section III,C,4,a,i), an excess of competing nucleophiles in reactions with secondary amines is undesirable. Thus, the interactions of l-ethyl-3-methyl-substituted salt 183 with 40% aqueous solution of dimethylamine leads to a-naphthol 189 as the major product (79TH1). 

The effect of substituents on C(2) of vinyl bromide and on the amine of the palladium catalyst in the. S n reaction with secondary amines was examined. The catalyst formed from the reaction of Pd2(dba)3 with proazaphosphatrane (12) gave the best yields (>91%) of enamine.16 The. S n product formed with primary amines rearranged to give the imine as the product in yields of >86%. 

Chlorine atoms may be substituted for amino groups by reaction with secondary amines (Equation 19) <1997JOM281>. 

Reaction with Secondary Amines Formation of IV-Nitrosoamines Secondary amines react with the nitrosonium ion to form secondary A-nitrosoamines, sometimes called nitrosamines. 

Examples include the synthesis of 3-amino-l,2,4-oxadiazoles starting from 3-acylamino-5-methyl-l,2,4-oxadiazole <2002H811> and 2-aryl-l,2,3-triazoles from l,2,4-oxadiazole-3-ketone arylhydrazones <1999T12885, 2006JOC5616>. Oximes, hydrazones, formamidines, and thioureas of the furazan series also undergo base-catalyzed mononuclear rearrangements <2004RCB1121>. Nucleophilic attack at N(3) takes place in the benzofuroxan series. For example, reaction with secondary amines leads to o-nitroarylhydrazines (Scheme 55). 

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