Wu, Ge et al. published their research in Organic Letters in 2013 | CAS: 827-01-0

5-Chloroindole-3-carboxaldehyde (cas: 827-01-0) belongs to indole derivatives. Indole, also called Benzopyrrole, a heterocyclic organic compound occurring in some flower oils, such as jasmine and orange blossom, in coal tar, and in fecal matter. It is used in perfumery and in making tryptophan, an essential amino acid, and indoleacetic acid (heteroauxin), a hormone that promotes the development of roots in plant cuttings.Computed Properties of C9H6ClNO

Regio- and Stereoselective Direct N-Alkenylation of Indoles via Pd-Catalyzed Aerobic Oxidation was written by Wu, Ge;Su, Weiping. And the article was included in Organic Letters in 2013.Computed Properties of C9H6ClNO This article mentions the following:

With two different sets of Pd catalyst systems in hand, indoles, whether bearing a C3-substituent or not, can be directly alkenylated on their nitrogen atoms using a sterically and electronically diverse array of alkenes, in which the high regio- and stereoselectivity are dependent on the nature of the alkenes used. This process proceeds in generally good yields and is compatible with a broad range of functional groups. Thus, a large series of N-alkenylated indoles, e.g., I, has been prepared In the experiment, the researchers used many compounds, for example, 5-Chloroindole-3-carboxaldehyde (cas: 827-01-0Computed Properties of C9H6ClNO).

5-Chloroindole-3-carboxaldehyde (cas: 827-01-0) belongs to indole derivatives. Indole, also called Benzopyrrole, a heterocyclic organic compound occurring in some flower oils, such as jasmine and orange blossom, in coal tar, and in fecal matter. It is used in perfumery and in making tryptophan, an essential amino acid, and indoleacetic acid (heteroauxin), a hormone that promotes the development of roots in plant cuttings.Computed Properties of C9H6ClNO

Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles