[H-].[Al+3].[Li+].[H-].[H-].[H-].[Cl-].[Al+3].[Cl-].[Cl-].[Cl:11][C:12]1[CH:30]=[CH:29][C:15]([CH2:16][C:17]23[O:28][C:18]2([C:24](OC)=[O:25])[C:19]([CH3:23])([CH3:22])[CH2:20][CH2:21]3)=[CH:14][CH:13]=1.C(OCC)C>COCCOC>[Cl:11][C:12]1[CH:13]=[CH:14][C:15]([CH2:16][CH:17]2[CH2:21][CH2:20][C:19]([CH3:22])([CH3:23])[C:18]2([OH:28])[CH2:24][OH:25])=[CH:29][CH:30]=12.7 g (71 mmol) lithium aluminium hydride were added to a suspension of 2.7 g (24 mmol) aluminium chloride partially dissolved in 120 ml 1,2-dimethoxyethane, the addition of lithium aluminium hydride causing a rise in temperature to 50° C. The resulting slurry was incubated at 50° C. for 30 minutes. A solution of 6.8 g (23 mmol) 1-(4-chlorobenzyl)-1,2-epoxy-3,3-dimethyl-2-methoxycarbonylcyclopentane prepared as described in Example 1 (g) in 30 ml 1,2-dimethoxyethane was then added over a period of 30 minutes whilst maintaining the temperature of the reaction mixture at 50°-55° C. After 1 hour, thin layer chromatography indicated that the reaction was complete and the excess lithium aluminium hydride was therefore destroyed by adding 10 ml saturated ammonium chloride solution followed by 10 ml water. This produced a sludgy solid which filtered only slowly. After filtration, the solid was dissolved in 2N hydrochloric acid and extracted twice with diethyl ether. The extracts were combined with the filtrate and flashed to give 5.9 g crude product. Trituration with cold 60/80 petroleum and a little diethyl ether gave 5.45 g 1-(4 -chlorobenzyl)-3,3-dimethyl-2-hydroxy-2-hydroxymethylcyclopentane as a white solid, m.pt. 103°-104° C. Yield: 82%.
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