3+2 Cycloaddition reactions of Carbohydrate Derived Donor Acceptor cyclopropanes

<p>Cyclopropane is a unique compound that exhibit features of both saturated and unsaturated hydrocarbons depending on the reaction partner(s) and circumstances used. One reason for the fascination for cyclopropane and its derivatives in organic synthesis is because many naturally occurring products and physiologically active substances have a three-carbon ring.1 Also the small size of the ring causes significant ring strain in the structure. Cyclopropanes being members of the cycloalkane family are known to engage in a wide range of reactions. The high strain energy of the three-membered ring allows it to participate in a variety of reactions. The discharge of this energy serves as a driving force for the ring to open. However it is difficult to polarize the C-C bonds of cyclopropane and many of its derivatives by itself. As a result the molecule requires reorganisation in terms of both electron distribution and geometry for elevated reactivity. The usual strategy for activating cyclopropanes is the insertion of substituents that enhance a desirable action. One such example is the incorporation of donor or acceptor or both the groups on the cyclopropane (</p>