摘要 |
<p>Preparation of optionally protected 4,8,8-trimethyl-1-oxaspiroÄ2.5Üoct-4-en-6-ol of formula (I) from the protected 4-hydroxy-2,6,6-trimethyl-2-cyclohexen-1-one of formula (II) comprises reaction with a halogenated methyl lithium, followed by optional deprotection. R = H or an OH-protecting group; R' = OH-protecting group.</p> |