An Efficient Synthesis for Some New Heterocyclic Compound‐fused Oxindole Derivatives

Abstract

An efficient and rapid procedure for the synthesis of novel oxindole derivatives is described. The process employs a condensation reaction of 3‐(bis(methyl thio)methylene)indolin‐2‐one and dinucleophiles such as 1,2‐phenylene diamine, propylene diamine, 2‐aminoethanol, ethylene‐1,2‐dithiol, 2‐mercaptoethanol, (1S,2S)‐cyclohexane‐1,2‐diamine, 2‐aminoethanthiol, 2,3‐diaminomaleonitrile, 2‐aminobenzenethiol, (3,4‐diaminophenyl)(phenyl)methanone, and ethane‐1,2‐diole in the presence of triethylamine under solvent‐free conditions at 60°C.

Catalyst‐Free Electrophilic Ring Expansion of N‐Unprotected Aziridines with α‐Oxoketenes to Efficient Access 2‐Alkylidene‐1,3‐Oxazolidines

“…Although 2‐(2‐oxoalkylidene)‐1,3‐oxazolidines have been widely applied as synthetic intermediates, their synthetic methods are very limited to date. The most common methods for synthesis of 2‐(2‐oxoalkylidene)‐1,3‐oxazolidines include: (a) the active methylene compounds with one or two electron‐withdrawing substituents reacted with carbon disulfide in the presence of strong bases followed by the methylation with methyl iodide or dimethyl sulfate to form α ‐oxoketene‐ S , S ‐ketals as intermediates, which further reacted with vicinal amino alcohols (Scheme 1a); [2f,g,3] (b) the active methylene compounds with two electron‐withdrawing substituents reacted with β‐chloroethyl isocyanate in the presence of Et 3 N or Na metal in dry DMF. In this method, alkyl isocyanates should have a leaving group on the β position of the alkyl group (Scheme 1b) [4] .…”

Triethylamine — A Versatile Organocatalyst in Organic Transformations: A Decade Update

“…165 Such structural motifs are present in several drugs like ropinirole and ziprasidone. In 2017, Mohammadi and co-workers 166 developed a solvent-free alternative route to a series of oxindole derivatives 80 and 81 on heating 3-[bis(methylsulfanyl)methylene]indolin-2-ones 78 with dinucleophiles 79 at 60 °C under the catalytic influence of triethylamine (Scheme 23). This protocol has the advantages of shorter reaction time, use of no other solvent, and yield of products over previous methods.…”