Ru(II)-Catalyzed C–H Aminocarbonylation of N-(Hetero)aryl-7-azaindoles with Isocyanates

Abstract

The ruthenium(II)-catalyzed C-H aminocarbonylation of N-(hetero)aryl-7-azaindoles with isocyanates is described. The excellent site selectivity at the ortho-position within the N-(hetero)aryl ring was observed to provide ortho-amidated N-(hetero)aryl-7-azaindoles under the mild reaction conditions. The resulting 7-azaindole derivatives can be readily transformed into 7-azaindoles containing carboxylic acid and alkyl amine functional groups.

Recent Advances in the N-Aryl C—H Functionalization Using 7-Azaindole as Intrinsic Directing Group

“…A variety of amidated N-(hetero)aryl-7-azaindoles were formed in good yields (Scheme 9). [19] This transformation features with a wide range of substrates with excellent site-and chemoselectivity under mild conditions. It is worth noting that the ortho-amidated N-(hetero)aryl-7-azaindole can be further converted into corresponding carboxylic acid and alkylamine derivatives.…”

Ru(II)‐Catalyzed ortho C—H Allylation of N‐Aryl‐7‐azaindoles with 2‐Methylidene Cyclic Carbonate

“…In the past few decades, transition‐metal‐catalyzed C—H functionalization has been proven to be an efficient strategy to construct N ‐aryl‐7‐azaindole moieties, because of its high atomic step economy and environmental sustainability. [ 3 ] To date, 7‐azaindole as a guiding group, transition‐metal‐catalyzed ortho C—H functionalization of aryl group, including amination, [ 4 ] sulfurization, [ 5 ] alkylation, [ 6 ] olefination, [ 7 ] alkynylation, [ 8 ] cyclization, [ 9 ] acylation, [ 10 ] cyanation/arylation, [ 11 ] have been extensively reported. Although significant progress has been made in the field, [ 12 ] the C—H allylation reaction of N ‐aryl‐7‐azaindole with 2‐methylidene cyclic carbonate has not been reported yet.…”

Ru(II)‐Catalyzed Selective C—H Alkynylation of Isoquinolones, Quinazolones and Phthalazinones with Bromoalkynes

“…On the other hand, the Ru(II) catalytic systems have increasingly been developed for the directed C-H activation because of their unique reactivity, lower cost, efficient catalytic systems, and promotion of new reaction pathways under milder reaction conditions. [15] On the basis, we envisioned that if using Ru(II) catalysis and bromoalkynes as the alkynylation reagents, the challenging heterocyclic compounds, such as isoquinolones, quinazolones and phthalazinones, would undergo directed C-H alkynylation. Herein, we report the first [RuCl 2 (p-cymene)] 2 -catalyzed directed C-H alkynylation of isoquinolones, quinazolones and phthalazinones with easily accessible alkynyl halides for producing alkynylated isoquinolones, quinazolones and phthalazinones (Scheme 1c).…”