Liane M. Klingensmith, M. Bio, G. Moniz
Nov 12, 2007
Citations
0
Influential Citations
22
Citations
Journal
Tetrahedron Letters
Abstract
Abstract An efficient synthesis of 4-methyl-2-thiopheneboronic anhydride is reported. Regioselective lithiation of 3-methylthiophene followed by reaction with triisopropylborate and hydrolysis provides a 92:8 ratio of 4-methyl-2-thiopheneboronic acid (1) and regioisomeric 2-methyl-3-thiopheneboronic acid (3). The undesired regioisomer is selectively protodeboronated with concentrated acid to provide only the desired 4-methyl-2-thiopheneboronic acid (1). The title compound is isolated by dehydration/crystallization and employed in several Suzuki–Miyaura reactions.