Boron Tribromide‐Assisted Chiral Phosphoric Acid Catalysts for Enantioselective [2+2] Cycloaddition. Issue 17 (30th April 2018)

• Record Type: Journal Article
• Authors: Sakamoto, Tatsuhiro; Mochizuki, Takuya; Goto, Yuta; Hatano, Manabu; Ishihara, Kazuaki
• Is Part Of: Chemistry, an Asian journal. Volume 13:Issue 17(2018)
• Page Start: 2373
• Page End: 2377
• Publication Date: 2018-04-30
• Subjects: [2+2] cycloaddition -- boron Lewis acid -- chiral Brønsted acid catalyst -- cyclobutane -- phosphoric acid; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/asia.201800351
• Languages: English
• ISSNs: 1861-4728

Abstract

Abstract: BBr3 ‐assisted chiral phosphoric acid catalysts for enantioselective [2+2] cycloaddition were developed. The reactions of phenyl vinyl sulfide with α‐substituted acroleins proceeded, and the corresponding [2+2] cycloadducts were obtained with high enantioselectivity. In particular, the [2+2] cycloadduct obtained from methacrolein is a synthetically useful optically active cyclobutane, which could be transformed to a key intermediate for (+)‐frontalin, a pheromone of Asian elephants. Abstract : Proton challenge : BBr3 ‐assisted chiral phosphoric acid catalysts were used for the enantioselective [2+2] cycloaddition of vinyl sulfides with acroleins. One of the obtained [2+2] cycloadducts could be readily transformed to a key intermediate for (+)‐frontalin as a pheromone of Asian elephants.