Development of efficient Lewis acid catalysts for intramolecular cycloaddition reactions of ester-tethered substrates.
We have developed novel bidentate Lewis acids that efficiently promote the intramolecular cycloaddition reactions of ester-tethered substrates. Bis-aluminated triflic amide derivatives [TfN(AlR(1)R(2))2], which are generated by simply mixing triflic amide and 2 equiv of methyl aluminum or aluminum hydride, catalyzed intramolecular Diels-Alder (DA) reactions of ester-tethered 1,7,9-trienes and intermolecular DA reactions of alpha,beta-unsaturated lactones. We also found that bimetallic Lewis acid derived from 1,1'-biphenyl-2,2'-di(triflyl)amide and dimethylaluminum chloride promoted the intramolecular [3 + 2] cycloaddition reaction of acrylate derivatives having an allylsilane part.
Taguchi
Takeo
T
School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1423-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan. taguchi@ps.toyaku.ac.jp
Saito
Akio
A
Yanai
Hikaru
H
D000535:Aluminum; D002384:Catalysis; D003500:Cyclization; D004987:Ethers / Q000737:chemistry*; D017611:Fluorine Compounds / Q000737:chemistry; D007202:Indicators and Reagents; D007783:Lactones / Q000138:chemical synthesis; D009942:Organometallic Compounds / Q000737:chemistry*; D012821:Silanes / Q000737:chemistry
D004987:Ethers; D017611:Fluorine Compounds; D007202:Indicators and Reagents; D007783:Lactones; D009942:Organometallic Compounds; D012821:Silanes; D000535:Aluminum