Reaction of 2-chloroindole-3-carbaldehyde with epihalogenohydrins. Tandem oxirane-opening—1,3-oxazole-closure process

Synthesis and Antimycobacterial Activity of Novel Thiadiazolylhydrazones of 1‐Substituted Indole‐3‐carboxaldehydes

“…The first step was introduction of a diverse set of substituents to N ‐1 position of indole‐3‐carboxaldehyde by a nucleophilic substitution reaction. According to the previous reports, a variety of bases such as sodium hydride, sodium/potassium hydroxide, and potassium carbonate in polar aprotic solvents such as dimethylsulphoxide, N,N ‐dimethylformamide, and acetone have been used to perform this reaction . The reaction has also been conducted in aprotic solvents such as dichloromethane using sodium hydroxide and an ammonium salt as phase transfer catalyst .…”

1H-Indole-3-carboxaldehyde: Synthesis and Reactions

“…The reaction of 1 with epichlorohydrin in DMSO in the presence of NaOH gives bi-1H-indole -3-carbaldehyde (54) on cooling [116] (Scheme 34). NaOH for 2 days gave bi-indole aldehyde (55) and tri-indole aldehyde (56), respectively [117,118] (Scheme 35).…”

Epihalohydrins in Organic Synthesis

“…According to a recent report, epichlorohydrin ( 5 ) and epibromohydrin ( 6 ) exhibit different reactivities toward 2-chloroindole-3-carboxaldehyde ( 261 ) under basic conditions (Scheme ) . Reaction with epibromohydrin ( 6 ) led to the selective formation of the corresponding 1-(oxiran-2-ylmethyl) derivative 262 by direct nucleophilic displacement of bromide, whereas the analogous reaction with epichlorohydrin ( 5 ) afforded the oxazolo[3,2- a ]indole skeleton 264 by initial epoxide ring opening, followed by a nucleophilic aromatic substitution.…”