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Updated: May 25, 2026
08:12
A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
(2E)-1-(5-Bromo-thio-phen-2-yl)-3-(2,3,4-trimeth-oxy-phen-yl)prop-2-en-1-one
Acta Crystallographica. Section E, Structure Reports Online
|January 20, 2012
Abstract:
In the title compound, C(16)H(15)BrO(4)S, the thio-phene ring is not coplanar with the benzene ring; the dihedral angle between the two planes is 11.08 (12)°. The crystal structure is characterized by C-H⋯O inter-actions. Weak intra-molecular C-H⋯O hydrogen bonds also occur.
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In organic synthesis, the formation of products can be altered by changing the reaction conditions. For example, a dibromo addition product is formed when propene is treated with bromine at room temperature. In contrast, propene undergoes allylic substitution in non-polar solvents at high temperatures to give 3-bromopropene. In order to avoid the addition reaction, the bromine concentration must be kept as low as possible throughout the reaction. This can be achieved using N-bromosuccinimide...
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