Synthesis of oxindolyl pyrazolines and 3-amino oxindole building blocks via a nitrile imine [3 + 2] cycloaddition strategy.
The [3 + 2] dipolar cycloaddition reaction of nitrile imines with 3-alkylidene oxindoles is described. The pyrazoline spiroadducts were obtained in high yields and with excellent regio- and diastereoselectivities. These spirocyclic intermediates have been elaborated to synthetically versatile 3-amino oxindole building blocks such as β-amino nitrile, 1,3-diamine, and pyrrolo[2,3-b]indoline derivatives.
Sanford-Burnham Medical Research Institute at Lake Nona, 6400 Sanger Road, Orlando, Florida 32827, USA.
Anand
A
Singh
Amanda L
AL
Loomer
Gregory P
GP
Roth
D000586:Amination; D061565:Cycloaddition Reaction; D007097:Imines / Q000737:chemistry*; D007211:Indoles / Q000138:chemical synthesis / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009570:Nitriles / Q000737:chemistry*; D000078183:Oxindoles; D011720:Pyrazoles / Q000138:chemical synthesis*; D013141:Spiro Compounds / Q000737:chemistry; D013237:Stereoisomerism
D007097:Imines; D007211:Indoles; D009570:Nitriles; D000078183:Oxindoles; D011720:Pyrazoles; D013141:Spiro Compounds; C022960:2-oxindole