Selective Synthesis of Dihalo‐Substituted Unsaturated Carboxylic Acids and Derivatives.

Abstract

2007 Halogenated carboxylic acids and esters P 0260 Selective Synthesis of Dihalo-Substituted Unsaturated Carboxylic Acids and Derivatives. -A new method for the selective formation of trans-dihalogenated alkenoic acids and acid derivatives is developed. -(LANGLE, S.; NGI, S. I.; ANSELMI, E.; ABARBRI, M.; THIBONNET, J.; DUCHENE*, A.; Synthesis 2007, 11, 1724-1728; Lab. Synth. Physicochim. Org. Ther., Fac. Sci. Tours, F-37200 Tours, Fr.; Eng.) -Jannicke 41-055

Straightforward Access to a Great Diversity of Complex Biorelevant γ-Lactams Thanks to a Tunable Cascade Multicomponent Process

“…Finally, in order to increase the molecular complexity of the γ-hydroxybutyrolactams, this process was also assessed starting from α,β-dihalogenoacrylic acids (Scheme ). In this case, the copper-mediated MCR furnished α-halogeno-γ-hydroxybutyrolactams, allowing postfunctionalization at the α-position by exploiting the reactivity of the resultant halogen atom. The utilization of α,β-dibromobutenoic acid or α,β-diiodobutenoic acid required a slight modification of the reaction conditions.…”

Synthesis and Biological Properties of 2(5H)-Furanones Featuring Bromine Atoms on the Heterocyclic Ring and/or Brominated Substituents

“…the light-driven transfer of electrons by chloroplasts in photosynthesis that results in the cleavage of water molecules and liberation of dioxygen [77]. Specifically, addition of bromine to 92 using a previously reported protocol [79] led to compound 93 in 93% yield. A mixture of 93 and 2.0 equiv of K 2 CO 3 in DMF was then stirred in the dark for 15 min and subsequently reacted with 2.0 equiv of arylacetylenes 94 and 0.2 equiv of CuI at 55-60 °C for 4 h under stirring.…”