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organic compounds
The structures of two trisubstituted 4-methylenecyclooctanones are reported, namely, di-tert-butyl 2-methoxycarbonyl-4-methylene-1-oxocyclooctan-6,6-dicarboxylate (IUPAC numbering: di-tert-butyl 5-methoxycarbonyl-3-methylene-6-oxocyclooctan-1,1-dicarboxylate), C21H32O7, (1) and di-tert-butyl 2-phenylsulfonyl-4-methylene-1-oxocyclooctan-6,6-dicarboxylate, C25H34O7S, (2). Compound (1) crystallizes with two independent molecules per asymmetric unit, adopting pseudo-centers of symmetry. The two independent molecules in the crystal have similar overall conformations. The two compounds differ in the torsion angles for the identical groups.