Potassium Hydroxide → HCID 68772153, compound

Reaction equation

[OH:1][C@@H:2]1[CH2:11][C:6]2([CH2:10][CH2:9][CH2:8][CH2:7]2)[C@@H:5]([C:12]([O:14]CC)=[O:13])[C:4]([CH3:17])=[CH:3]1.[OH-].[K+].[OH-].[Na+]>C(O)C>[OH:1][C@@H:2]1[CH2:11][C:6]2([CH2:7][CH2:8][CH2:9][CH2:10]2)[C@@H:5]([C:12]([OH:14])=[O:13])[C:4]([CH3:17])=[CH:3]1

Participants

Procedure

A 33:67 cis-/trans-ethyl 9-hydroxy-7-methylspiro[4.5]dec-7-ene-6-carboxylate (38 g, 0.16 mol, prepared as described in Example 16) was added to a solution of KOH (52.6 g, 0.8 mol) in ethanol (300 ml). The resulting mixture was stirred for 2 h at reflux, poured into cold 2N aqueous NaOH (100 ml), and extracted twice with MTBE (100 ml). The combined organic phases were washed with 2N aqueous NaOH (50 ml), the combined aqueous phases were acidified with conc. HCl, extracted twice with MTBE (150 ml), and the combined organic phases were washed with water (100 ml), with a saturated aqueous solution of NaCl (100 ml), dried (MgSO4), and concentrated, giving crude trans-9-hydroxy-7-methylspiro[4.5]dec-7-ene-6-carboxylic acid (22.7 g).