| Summary: | 碩士 === 國立交通大學 === 應用化學系 === 83 === The reduction of 5-substituted-adamantan-2-one (5-X-ADs) by
NaBH4 is found to favor the syn-pi-face attack of nucleophile
due to electronwithdrawing substituents. In the present of beta-
cyclo- n(beta-CD),5-X-AD can form an inclusion complex with the
hydrophibic cavity of CD.This leads to the protection of syn-
pi- face of 5-X-AD and a reversed face selectivity was
observed. Beside Cl and Br substituents, we also added bigger
substituents as SnMe3 and different substituted phenyl
groups. Our results show that, for small substituent (such as
F), beta-CD has almost no effect on pi-face selectivity,
however, for large substituent such as SnMe3, enhanced syn-
attack was found. In this work, we also use seneral modified
beta-CDs in combination with different 5-X-ADs to study their
size and shape relationships for inclusion complexes and their
effects on face selectivity. 2-Br and 2-Cl are found to undergo
SN1 rection in the process of basic reduction (NaBH4 and 0.01 N
NaOH);i.e. Br- and Cl- substituents arereplaced by -OH. All
beta-CDs studied here can protect 2-Br and 2-Cl form SN1
reaction no matter whether they change the face-selectivity or
not. H-NMR was used to prove the inclusion complex formation of
5-acryl-ADs with beta-CDs.
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