Indole-2-carboxamides

Indole-7-carbaldehyde, 1-methyl-synthesis, 4, 83 Indole-3-carbaldehydes synthesis, 2, 251 Indole-2-carboxamide reduction, 4, 256 synthesis, 4, 360 Indole-3-carboxamide synthesis, 4, 347... 

Indole-3-carbonitrile has been prepared by the dehydration of indole-3-carboxaldehyde oxime,8 5 indole-3-glyoxalic acid oxime,58 or indole-3-carboxamide 8 by the action of cyanogen... 

Carlock, J.T., Bradshaw, J.S., Stanovnik, B. and Tisler, M. (1977) 3-Diazo-4-oxo-3,4-dihydroquinoline. A novel synthon for indole-3-carboxamides. Journal of Organic Chemistry, 42 (11), 1883-1885. 

Reductive cyclization of nitrocyano derivatives provides an elegant entry to a variety of indole-3-carboxamides by formation of a five member ring amine ... 

This result is not surprising since it was shown earlier that trichloromethyl ketones react more rapidly with methanol (alcohols) than with water under alkaline conditions.29 The ethanolic cleavage of a trichloromethyl ketone has been used to prepare ethyl 3,3-diethoxypropanoate,30 and aryl trifluoromethyl ketones can be cleaved to give carboxylic acids or esters.31 A similar reaction of 3-trifluoroacetylindole (19) with lithium dialkylamides affords good yields of the corresponding indole-3-carboxamides (20).3... 

Pyrido[3,4-/3]indole-3-carboxamide, A/-methyl- XIII-1, XVII.E-8 ... 

Reaction with indoles. The reagent reacts with indole or 2-substituted indoles (1) to form the derivatives 2, which can be converted into indole-3-carboxamides (3) or into indole-3-carbonitriles (4). The compounds are versatile precursors to 3-substituted indoles. 

In the same series of papers, Knight also investigated the selective C2-lithiation of indole-3-carboxamides [326, 327]. In this case, n-butyllithium (slight excess) was used as the base instead of LDA. Treatment of indole-3-carboxamides 103 with n-butyllithium followed by electrophiles gave 2,3-(disubstituted)indoles 104. A portion of the results obtained are shown below (Table 20). Snieckus used a directed lithiation of 103c to prepare the corresponding indole-2-boronic acid, a useful building block for the synthesis of indolocarbazoles [329]. 

R= -Bu) afforded l,3-benzodiazepin-4-one (22). With 15 (R=cyclohexyl), amixture of indole-3-carboxamide (25%) and l,3-benzodiazepin-4-one (58%) was obtained. The latter cyclized product probably arises from a nitrogen-copper species. In a full account of their indole syntheses methodology, Saegusa presented more examples of the chemistfy already given in this chapter, plus a new application was the synthesis of 2,3-disubstituted indoles 24. Thus, as shown in equation 4 (Scheme 3) base-induced alkylation of ortto-(acylmethyl)phenyl isocyamides 10 prior to cyclization led to 2,3-disubstituted indoles 24 [5]. 

The copper-catalyzed methodology for arylation of indoles was utilized in the C3-arylation of A -tosyl tryptamines and tryptophan derivatives to yield pyrroloindolines in a diastereoselective fashion [227,228], and similar transformations were achieved with tryptophols [229, 230]. MacMillan s group developed an asymmetric copper bisoxazoline-catalyzed C3-arylation of indole-3-carboxamides, where the intermediate indole iminium ion was intramolecularly attacked by the amide substituent to form tricyclic pyrroloindolines with high enantioselectivities and good yields (Scheme 17b) [193]. 

ArCH=NPhO to bis-(trifluoromethyl)-acetylene rearrange to the oxazolines (318), which, on hydrolysis and subsequent cyclisation, yield the indole (319). Indole-3-carboxamides (322 R R = H, alkyl, or Ar) are produced by irradiating the diazo-ketones (320) in the presence of amines HNR R the Wolff rearrangement product (321) is a likely intermediate in this reaction. Crossover experiments show that the thermal rearrangement of the 3if-indole (323) to... 

ADBICA N-(1 -Amino-3,3-dimethyl-1 -oxobutan-2-yl)-1 -pentyl-1 H-indole-3-carboxamide... 

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