1,1-Dichlorocyclopropane derivatives of α and β ionones. Structure determination of 3R,3′S-bis[3-methyl-5-(1′,3′,3′-trimethylcyclohex-1′-en-2′-yl)-2(1H)-furanone]

1,1-Dihalocyclopropane derivatives and furanones were synthesized from ±α- and β-ionones using CHCl3, NaOH, and triethylbenzyl ammonium chloride (TEBAC). 2D NMR and single-crystal X-ray analyses of the products are reported. Keywords: addition of 1,1-dihalocarbenes to ionones, phase transfer addition of 1,1-dihalo systems, formation of cyclopropanes.