Ytterbium(III)‐Catalyzed Addition Reaction of Alkynyltrifluoroborate Salts to α‐Imino Esters: Efficient Synthesis of β‐Unsaturated α‐Amino Esters. Issue 6 (11th December 2013)

• Record Type: Journal Article
• Authors: Stefani, Hélio A.; Manarin, Flávia; Khan, Amna N.; Vasconcelos, Stanley N. S.
• Is Part Of: European journal of organic chemistry. Issue 6(2014)
• Page Start: 1236
• Page End: 1240
• Publication Date: 2013-12-11
• Subjects: Synthetic methods -- Lewis ­acids -- Schiff bases -- Alkynes -- Boron -- ­Ytterbium; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201301421
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract: We describe the development of a mild and efficient method for the preparation of β‐unsaturated α‐amino esters through the ytterbium triflate catalyzed addition of potassium alkynyltrifluoroborate salts to imino esters. The synthetic viability of this protocol was supported by its high yields, short reaction times, and efficiency with regard to the scope of the substrates. Abstract : We present a general approach for the synthesis of β‐unsaturated α‐amino esters by addition of alkynyltrifluoroborates to imines catalyzed by ytterbium triflate [Yb(OTf)3 ]. The catalyst can be separated from the reaction medium by simple filtration and recycled.