3-tert-Butyl-2-oxo-1-oxaspiro[4.5]dec-3-en-4-yl 4-chlorobenzoate

Abstract

The title tetronic acid derivative, C20H23ClO4, which is a spirodiclofen analogue, has two crystallographically independent molecules in the asymmetric unit (Z′ = 2). The cyclohexane rings in the respective molecules A and B adopt chair conformations [four C atoms are planar with mean deviations of 0.013 (2) and 0.001 (2) Å, and the flap positions deviate by 0.653 (4) and −0.663 (3) Å (molecule A) and 0.642 (4) and −0.643 (5) Å (molecule B) from the plane]. The furan ring makes dihedral angles of 86.9 (1) (molecule A) and 85.4 (1)° (molecule B) with the respective benzene rings.