Cyclizations producing hydrindanones with two methyl groups at the juncture positions mediated by samarium diiodide and electrolysis.

One-electron reductive intramolecular cyclization of enones with ketones or aldehydes mediated by samarium diiodide and electrolysis to afford cis-trimethyl- hydrindanolones. The reactions gave selectivities ranging from 1:1 to 100:0 depending on the conditions.