Arylamines Mannich reaction

Xiu-Juan, X. and Guang-Xu, C., Mannich reaction of arylamines. Acta Chim. Sinica, 40,... 

Further examples of Mannich reactions aimed at the modification of materials range from the use of suitable aldehyde mixtures in the crosslinking of proteins for contact Icnscs-- to the modification of rcsols with arylamines - for obtaining rapidly curing resins employed as wood adhesives. Some further examples of the functionalization of macromolecular derivatives for modifying the final properties of the material are found in Chap. Ill, D. 

The Mannich reactions of arylamines have not been studied in as much detail as those of phenols. Nevertheless, interesting features have been established and further developments can be envisaged. 

See, for instances (a) S. Santra, R R. Andreana, Org. Lett. 2007, 9, 5035-5038. A one-pot, microwave-influenced synthesis of diverse small molecules by multicomponent reaction cascades, (b) M. Presset, Y. Coquerel, J. Rodriguez, Org. Lett. 2009, 11, 5706-5709. Microwave-assisted domino and multi-component reactions with cyclic acyUcetenes expeditious syntheses of oxazinones and oxazindiones. (c) W.-J. Hao, B. Jiang, S.-J. Tu, X.-D. Cao, S.-S. Wu, S. Yan, X.-H. Zhang, Z.-G. Han, F. Shi, Org. Biomol. Chem. 2009, 7,1410-1414. A new mild base-catalyzed Mannich reaction of hetero-arylamines in water highly efficient stereoselective synthesis of 3-aminoketones under microwave heating, (d) P. Nun, J. Martinez, F. Lamaty, Synthesis 2010, 2063-2068. Microwave-assisted neat procedure for the Petasis reaction. 

Photolysis of acylated arylamines 6-16 Reaction between aldehydes, ammonia, and aldehydes, ketones, or esters (Mannich)... 

The behavior of thioatnides (70, Table 8) is influenced by tautomeric effects. In the case of bis-aminomcthylation of 2-imidazolidinothionc, - for extunplc, the mobile H atom can be selectively substituted in both the forms by reaction with secondary di-alkylamincs, or primary arylamines, to give, respectively, N,N- (A attack) or N,S- (B attack) bis-Mannich bases. 

The results (Table 9) indicate that the Mannich bases deriving from attack on the less substituted C atom arc obtained more frequently, the B attack being preferred only under particularly selected reaction conditions, such as the use of mcthyleneimmonium salts in dilute trifluoroacetic acid solution for very long reaction times " or with ethanolic primary arylamine hydrochlorides.- However, few exceptions to the prevailing behavior have been observed. - - ... 

Arylamines 79 are allowed to react under acidic conditions, in the presence of acetic acid, which affects even Ihe chemosclectivity of the reaction with formation of N-Mannich base when the molar ratio acid/sub.strate is very low (1 25). " ... 

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