Plecton ,Guidotti, Italy ,1975
ChEBI: (1S,2R)-cicloxilic acid is a 2-hydroxy-2-phenylcyclohexanecarboxylic acid that has (1S,2R)-stereoconfiguration. It is an enantiomer of a (1R,2S)-cicloxilic acid.
25 g of 2-hydroxy-methyl-cyclohexanone, diluted in 20 cc of ether, were
dropped into a vessel containing an ether suspension of phenyl-magnesiumbromide (prepared from 19.6 g of magnesium and 128 g of bromobenzene in
300 cc of ether according to usual techniques by stirring and external icecooling). The mixture was stirred for some time, then the magnesium
compound was decomposed by pouring it carefully into water and ice; the
magnesium hydroxide was dissolved in 50 cc of a saturated solution of
ammonium chloride, the ether portion was separated and the aqueous portion
extracted with further ether.
Collected and dried ether extracts were evaporated and the residue vacuum
distilled yielded 15 g of a thick oil of boiling point at 0.1 to 0.2 mm Hg 127°C
to 135°C.
This product crystallized by dissolving in ether and reprecipitation with
petroleum ether yielded 7 g of 1-phenyl-2-hydroxy-ethylene-cyclohexan-1-ol,
melting point (Kofler) 81°C to 83°C.
The thus obtained product was dried and finely powdered, and then
suspended in 1.4 liters of an aqueous solution of 14 g of KMnO4 and 7 g of
N2CO3, and the suspension was thoroughly stirred for one day.
After filtering off the MnO2, thus formed, a small amount of Na2SO3 was
added until the violet coloration disappeared; MnO2 was filtered again and the
alkaline solution was acidified with concentrated HCl.
After one day standing in a refrigerator, the product was filtered and washed
with water, thus yielding 5 g of 2-phenyl-2-hydroxy-cyclohexane-carboxylic
acid, melting point (Kofler) 143°C to 145°C.
