Expanding the scope of arylsulfonylacetylenes as alkynylating reagents and mechanistic insights in the formation of Csp2-Csp and Csp3-Csp bonds from organolithiums.
We describe the unexpected behavior of the arylsulfonylacetylenes, which suffer an "anti-Michael" addition of organolithiums producing their alkynylation under very mild conditions. The broad scope, excellent yields, and simplicity of the experimental procedure are the main features of this methodology. A rational explanation of all these results can be achieved by theoretical calculations, which suggest that the association of the organolithiums to the electrophile is a previous step of their intramolecular attack and is responsible for the unexpected "anti-Michael" reactions observed for substituted sulfonylacetylenes.
Departamento de Química Orgánica (Módulo 1), Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain. joseluis.garcia.ruano@uam.es
José Luis
JL
García Ruano
José
J
Alemán
Leyre
L
Marzo
Cuauhtémoc
C
Alvarado
Mariola
M
Tortosa
Sergio
S
Díaz-Tendero
Alberto
A
Fraile
D000480:Alkynes / Q000138:chemical synthesis / Q000737:chemistry*; D002384:Catalysis; D007202:Indicators and Reagents; D008094:Lithium / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D009942:Organometallic Compounds / Q000737:chemistry*
D000480:Alkynes; D007202:Indicators and Reagents; D009942:Organometallic Compounds; D008094:Lithium