One‐pot Construction of Dibenzooxabicyclo[5.5.0]dodecanes

Abstract

Under the open‐vessel atmosphere conditions, the one‐pot synthesis of bis‐sulfonyl dibenzooxabicyclo[5.5.0]dodecanes was developed by double substitution of 1,3‐dichloroacetone with arenesulfinic acid sodium salts, and C‐ and O‐alkylation of the resulting 1,3‐bis‐sulfonylacetones with 2 equivalents of o‐bis(bromomethyl)arenes. A plausible mechanism is proposed and discussed. This high‐yielding protocol provides an intermolecular substitution and an intramolecular ring‐closure via the formations of three carbon−carbon single (C−C) bonds, two carbon−sulfur single (C−S) bonds, and one carbon−oxygen single (C−O) bond.

K2CO3-mediated annulation of 1,3-acetonedicarboxylates with 2-fluoro-1-nitroarenes: synthesis of indoles

“…Based on our previous studies on the tandem annulation of 1,3-diacetonecarbonyls ( e.g. , the synthesis of arylphenols, 5-aryl-4-arylidene-2-cyclohexenones, and dibenzooxabicyclo[5.5.0]dodecanes), 18 we developed a one-pot high-yield K 2 CO 3 -mediated simultaneous synthesis of substituted indoles 4 via the annulation of 1,3-acetonedicarboxylates 2 with 2 equiv. of substituted 2-fluoro-1-nitrobenzenes 3 under open-flask atmospheric conditions.…”