Unsymmetrically substituted alpha-hydroxy ketones possessing isoprenoid units within the molecule were synthesised from commercially available terpene aldehydes. The synthesis was applicable to alpha,beta-unsaturated aldehydes and afforded the respective a-hydroxy-methyl ketones in overall good yield. Tautomerisation of these products did not occur under the conditions of reaction but was observed upon heating. Diastereoisomeric alpha-hydroxy ketones have been resolved, and X-ray analysis on one of these analogues allowed for the elucidation of the stereochemistry after conversion into its camphanate ester.
- alpha-hydroxy ketones
- terpene aldehydes
- cyanohydrin trimethylsilyl ethers
- copper salt catalysis
- Grignard reaction