Iman, Muhammad Zaki (2006) Internally hydrogen-bonded chiral methylenenitrones in cycloaddition reactions. Masters thesis, King Fahd University of Petroleum and Minerals.
1,3-Dipolar cycloaddition (DC) reactions of two chiral methylene nitrones, (R)-N-2-(1-hydoxy-2-phenyl ethyl)methylenenitrone (I) and (1R,2S,3R,4R)-N-3-(2-hydroxy-1,7,7-trimethylbicyclo[2.2.1]heptanyl)methylenenitrone (II), with a multitude of mono-, di-, and tri-substituted alkenes have been studied in detail. The nitrone (II) showed better face and stereoselectivity. The stereochemical outcome has been explained in terms of steric factors and secondary orbital interactions in the transition states. The effect of intramolecular hydrogen bonding has also been demonstrated. The DC reactions of the nitrone (I) in the presence of magnesium bromide have exhibited remarkable regio- and stereoselectivity. The improved selectivity has been rationalized using a metal chelated cyclic form of the nitrone. The findings of the study would indeed be useful in incorporating chiral centers in natural product synthesis.
|Item Type:||Thesis (Masters)|
|Divisions:||College Of Sciences > Chemistry Dept|
|Creators:||Iman, Muhammad Zaki|
|Committee Advisor:||Ali, Shaikh Asrof|
|Committee Members:||Fettouhi, M. B. and Al-Muallem, Hasan A.|
|Deposited By:||KFUPM ePrints Admin|
|Deposited On:||22 Jun 2008 17:07|
|Last Modified:||30 Apr 2011 15:36|
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