pi-Facial selectivity in 1,3-dipolar cycloaddition reactions of alpha-methylidene-gamma-lactone substituted by 4-methyl-2,6,7-trioxabicyclo[2.2.2]octanyl group in gamma-position
| Authors | |
|---|---|
| Year of publication | 2002 |
| Type | Article in Periodical |
| Magazine / Source | Collection of Czechoslovak Chemical Communications |
| MU Faculty or unit | |
| Citation | |
| Web | http://cccc.uochb.cas.cz |
| Field | Organic chemistry |
| Keywords | 1;3-dipolar cycloadditions; methylene lactones; stereoselective synthesis; spiro compounds; ortho esters |
| Description | Diastereoselectivity of 1,3-dipolar cycloaddition reactions of benzyl azide, diazomethane, a nitrile oxide and a nitrile imine to alpha-methylidene-gamma-lactone dipolarophile was effectively controlled by a bulky substituent, 4-methyl-2,6,7-trioxabicyclo[2.2.2]octan-1-yl (OBO), in gamma-position of the dipolarophile. The dipoles added from the less hindered face of the double bond with an excellent selectivity. The enantiomerically pure dipolarophile was prepared from the easily available (S)-5-oxotetrahydrohydrofuran-2-carboxylic acid. |
| Related projects: |