1,4-ADDITION OF LITHIUM ORGANYLS TO PARA-QUINOLS STRUCTURE DETERMINATION OF RT-BUTYL-4-HYDROXY-4,5-DIPHENYLCYCLOHEX-2-EN-1-ONE

Addition of lithium organyls to sterically hindered para-quinols leads to 1,2- or 1,4-adducts. The 1,4-addition prevails, if the 4-substitue nts in the quinol and the organic group in the lithium organyl are lar ge. Four 1,4-addition products (2-cyclohex-2-en-1-ones) are synthesize d and their structures investigated by NMR spectroscopy. The aryl grou ps at C-4 and C-5 acquire equatorial positions, the alkyl group at C-6 is bisectional. These results are confirmed by X-ray analysis of t-bu tyl-4-hydroxy-4,5-diphenylcyclohex-2-en-1-one, revealing a twist boat conformation of the cyclohexene ring.