Naslov
Reduction of adamantanone : face selection induced by 4-halo- and 4, 9-dihalo- substitution

Autori
Kaselj, Mira ; le Noble, William J.

Izvornik
Journal of organic chemistry (0022-3263) 61 (1996), 12; 4157-4160

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
bicyclo[2.2.2]octane ring-system ; nucleophilic-addition ; F-19 nmr ; hyperconjugation ; stereochemistry ; oxygenation ; solvolysis

Sažetak
Our studies of the stereochemistry of addition and elimination as well as those of several other groups have been based largely on the reactions of 2-adamantylidenes bearing substituents in the 5- and/or 7-positions. In these probes, the two faces at C-2 are thereby rendered electronically different while steric equivalence is maintained. We find that attack of all reagents at C-2 occurs at the zu face if an electron-withdrawing substituent is located at C-5, while we interpret as an indication that transition state hyperconjugation controls the stereochemistry. Since the product or rate ratios are usually rather modest, the though arose that, perhaps, substantially more robust effects might be expected from substituents located at C-4 and C-9. In the axial positions of these secondary carbons, substituents will clearly influence face selection at C-2 sterically, but in the equatorial ones, they should not.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA