Radical mediated oxidations in organic chemistry. 3. An efficient and versatile transformation of aldehydes into amides ¥.

Heterobimetallic clusters of Na8Ln(OtBu)10(OH) as homogeneous catalysts for amidation of aldehydes with amines

“…The direct amidation of aldehydes with amines is the most desired approach to amides because it is economical and starting materials are readily available. Various efficient catalysts have been explored for this process [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]; however, some of these systems require the use of peroxide [2,3], heating, or equivalent alkali metal amides [5]. Since the first example of amidation of aldehydes with amines catalyzed by homoleptic lanthanide amides was reported [17], various lanthanide complexes, such as tris-guanidinate lanthanide complexes [18], bis-amidinate lanthanide complexes [19] and anionic lanthanide aryloxides [20], have been shown to behave as efficient catalysts under mild conditions.…”

The preparation of N-acylbenzotriazoles from aldehydes

“…(Scheme 1) This resembles the known reaction of aldehydes with N-bromosuccinimide to give the corresponding acid bromides using catalytic amount of AIBN as a radical initiator. 15 Results are shown in Table 1. Known products were identified by m.p.…”

“…12 In cases where the aldehyde is more readily available than the corresponding carboxylic acid, it is convenient to carry out the conversion of aldehyde RCHO into an acylating agent RCOX. Indeed, a number of methods are available for the direct conversion of aldehydes to the corresponding acid halides: (i) by the treatment of aromatic aldehydes with SO 2 Cl 2 in the presence of a phosphonium catalyst; 13 (ii) use of N-chlorosuccinimide; 14,15 (iii) carbon tetrahalides at high temperatures; 16 (iv) vapor phase photochemical halogenation; 17 and (v) iodobenzene dichloride. 18 N-Chlorobenzotriazole has been widely used as (i) a mild oxidant 19,20 for the preparation of aldehydes, ketones, 21 azo-compounds, 21 sulphoxides, 20 sulfonimidoyl chlorides, 22 nitrile oxides; 23 (ii) a chlorinating agent 24,25 and (iii) for addition reactions to olefins [26][27][28] and isonitriles.…”

“…26 We now show that N-chlorobenzotriazole (2) conveniently converts aldehydes 1a-g into the corresponding N-acylbenzotriazoles 3a-g (Scheme 1). Alcohols 8a and 8h are also converted into acylbenzotriazoles (Scheme 4), while substituted toluenes give the corresponding Nalkylbenzotriazoles 10a-c. All these reactions take place in the presence of AIBN 15 as a radical initiator.…”

FeCl2-Catalyzed Oxidative Amidation of Aldehydes with Primary and Secondary Amines

“…[7] Three strategies have been developed for amide bond formation using aldehydes and primary or secondary amines as starting materials (Scheme 1). The aldehydes are activated through acyl bromide, [8] acyl cyanide, [9] nitrile, [10] or active ester [11] as intermediate to couple with amines (Strategy I). Amines can also be transformed into N-chloroamines [12] and anionic amido complex [13] which play as active intermediates to react with aldehydes (Strategy II).…”