A library of pinane-based aminodiols were prepared from commercially available (1R)-(-)-myrtenol (-)-1. Compound (-)-1 was transformed into allyl trichloroacetamide (+)-2 via the acetimidate, followed by the Overman rearrangement. In order obtain the aminodiol structure, (+)-2 was subjected to stereoselective dihydroxylation with OsO 4, resulting in dihydroxy trichloroacetamide (+)-3. The trichloroacetyl group was removed from (+)-3 with aqueous HCl, and the (1R,2R,3S,5R)-3-amino-2-hydroxymethyl-6,6- dimethylbicyclo[3.1.1]heptan-2-ol hydrochloride (-)-4 obtained was transformed to primary, secondary and tertiary aminodiols by reductive amination, N-alkylation of aminodiol (+)-9 and debenzylation of N-benzyl aminodiol (+)-10, respectively. In the reactions of (+)-9 and (+)-14 with formaldehyde, highly regioselective ring closure was observed. In contrast with earlier results, the aminodiols gave pinane-fused oxazolidines (+)-11 and (-)-15. The aminodiols and their oxazolidine derivatives 5-15 were applied as chiral catalysts in the enantioselective addition of diethylzinc to benzaldehyde. The best enantioselectivity was observed in the case of the N-benzyl-substituted derivative (+)-9.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry