Direct synthesis of aryl substituted pyrroles from calcium carbide: an underestimated chemical feedstock

Abstract

In this work, a novel synthetic methodology for the preparation of aryl pyrroles directly from the reaction of calcium carbide with oxime is reported.

Calcium Carbide: A Unique Reagent for Organic Synthesis and Nanotechnology

“…A new procedure for the synthesis of arylpyrrols was elaborated based on acetylene that was generated from calcium carbide (Scheme ) . Vinylation products were formed in some cases; however, the yield of these adducts was less than 5 %.…”

Calcium‐Based Sustainable Chemical Technologies for Total Carbon Recycling

“…Various pyrrole derivatives can be obtained from available oximes and calcium carbide in satisfactory yields . The reaction proceeds in DMSO/water medium, in the presence of a base and with [18]crown‐6 as a ligand.…”

“…Various pyrrole derivatives can be obtained from available oximes and calcium carbide in satisfactory yields. [69] The reac- Scheme2.Production of monosubstituteda ryl 1,2,3-triazolesf rom calcium carbide and ad iazonium salt. tion proceeds in DMSO/waterm edium, in the presenceo fa base and with [18]crown-6 as al igand.…”

An Atom‐Economic Approach for Vinylation of Indoles and Phenols Using Calcium Carbide as Acetylene Surrogate

“…Key features of this reaction include the use of calcium carbide as a safe and inexpensive slow released acetylene source for N-and O-vinylation under simple reaction conditions without the need for metal catalyst or halogenated substrates. [11] Calcium carbide has similarly been used in the generation of vinyl thioesters from Svinylated thiophenols [12] as well as vinyl alcohols from O-vinylated aliphatic alcohols. [10] Recently, calcium carbide was used as an electrophilic precursor in a vinylation reaction to produce vinylic derivatives such as O-vinyloximes, which could further cyclize into 2-arylpyrroles.…”

“…[10] Recently, calcium carbide was used as an electrophilic precursor in a vinylation reaction to produce vinylic derivatives such as O-vinyloximes, which could further cyclize into 2-arylpyrroles. [11] Calcium carbide has similarly been used in the generation of vinyl thioesters from Svinylated thiophenols [12] as well as vinyl alcohols from O-vinylated aliphatic alcohols. [13] N-Vinylindole derivatives are widely used as monomers for polymeric [14] and photoactive [15] materials.…”