Synthesis of highly functionalised spiro-indoles by a halogen atom transfer radical cyclization.
The halogen atom transfer radical cyclization (HATRC) has been evaluated on N-(indolylmethyl)trichloroacetamides under Cu(I)Cl catalysis using nitrogen containing ligands. The ring closure leads to the formation of 3,3-spiro-3H-indoles in moderate to good yields by a 5-exo-mechanism. Derivatives with an N-electron withdrawing substituent also lead to a 5-exo-trig and not to a 6-endo-trig cyclization.
Stevens
Christian V
CV
Research Group SynBioC, Department of Organic Chemistry, Faculty of Bioscience Engineering, Ghent University, Belgium. Chris.Stevens@Ugent.be
Van Meenen
Ellen
E
Eeckhout
Yves
Y
Vanderhoydonck
Bart
B
Hooghe
Wim
W
D003300:Copper / Q000737:chemistry*; D003500:Cyclization; D005609:Free Radicals / Q000737:chemistry; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D008024:Ligands; D015394:Molecular Structure; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
D005609:Free Radicals; D007211:Indoles; D008024:Ligands; D013141:Spiro Compounds; D003300:Copper; C028419:cuprous chloride; C029892:cupric chloride