Alkylation-annulation of halo esters with organometallic reagent/SmI2 couple leading to cycloalkanols: A facile cyclopropanol synthesis from a 3-halo ester

Transformation of a 3-halo ester to cyclopropanols has been accomplished in excellent yields under mild conditions employing a coupled reagent of samarium(II) diiodide with organometallic reagents. 5- and 6- Halo esters were also transformed into cyclopentanols and cyclohexanols, respectively, in low to moderate yields. The reaction with a 4-halo ester gave 2,2-disubstituted tetrahydrofuran as a major product that resulted from double alkylation followed by cyclization; a substituted cyclobutanol was formed in poor yield.