本研究運用半經驗及ab initio的量子力學理論計算方法研究5-substituted-2-dicyanomethyleneadamantanes及5-aza-2-dicyanomethyleneadamantane N-oxide分別與CH3MgCl及PhCH2MgCl反應之π面選擇性，所探討的取代基包含-F, -Cl, -Br, -OH, -NH2, -OMgCl, -CH3及-Si(CH3)3，結果顯示，除了-Si(CH3)3外，其餘取代基化合物皆較易進行syn的反應，而計算所得-F, -Cl, -Br之syn/anti attack的產物比例與實驗有很好的一致性，在所用的PM3, HF及B3LYP方法中，HF的方法與實驗的一致性最好。
此外，由NBO分析方法發現，與親核劑CH3MgCl的反應中，過渡態之hyperconjugative σCα-Cβ→σ*C-Nu interactions造成的穩定化能量與π面選擇性有高相關度；在與PhCH2MgCl的反應中，-F, -Cl, -Br之結果顯示，由σCα-Cβ→π*C-C超共軛作用力造成的穩定化能量是影響π面選擇性的一重要因素，而-OH及-NH2之π面選擇性除了與上述超共軛效應有關，取代基與PhCH2MgCl之苯環間的靜電作用力亦是一重要因素，-OMgCl則主要由Mg與苯環的靜電作用力決定面的選擇性。在5-aza-2-dicyanomethyleneadamantane N-oxide與Grignard reagents的反應中，除了上述的超共軛效應外，結構效應亦是影響π面選擇性的一重要因素。

The π-facial selectivity in the reactions of 5-substituted-2-dicyanomethyleneadamantanes and 5-aza-2-dicyanomethyleneadamantane N-oxide with the Grignard reagents, CH3MgCl and/or PhCH2MgCl were examined using semiempirical and ab initio calculation. The substituents investigated include -F, -Cl, -Br, -OH, NH2, -OMgCl, -CH3 and -Si(CH3)3. The reactions for all substituents, except the -Si(CH3)3 group, favor syn attack. The calculated syn/anti product ratio for the substituents of -F, -Cl, -Br groups agree well with available experimental results. The results obtained from the PM3, HF and B3LYP methods show that the HF results agree with the experimental results better than the other two methods.
In addition, the results of employed NBO analysis show that the stabilization energy due to the hyperconjugative σCα-Cβ→σ*C-Nu interactions at the transition state correlates well withπ-facial selectivity in the reactions of 5-substituted-2-dicyanomethyleneadamantanes with CH3MgCl. The calculated results for the reaction with PhCH2MgCl appear that the strength of the hyperconjugative σCα-Cβ→π*C-C interactions at the transition state plays a significant role in π-facial selectivity for the substituents of -F, -Cl, -Br groups. Besides the hyperconjugation described above, the electrostatic interactions between the benzyl group of PhCH2MgCl and -OH and/or -NH2 groups in the 5-substituted-2-dicyanomethyleneadamantanes are also a significant factor in the π-facial selectivity. The calculations of 5-aza-2-dicyanomethyleneadamantane N-oxide also gave results that structural effects, as found in previous study, affect the syn/anti product ratio significantly in the π-facial selectivity.

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