Natural product synthesis organic electrophiles

It is the hope of the authors that the compilation of the results gained hitherto in the field of electrophilic cyclopropanes will stimulate further interest in this area. The numerous reactions described in this survey article are an indication of the potential of the title compounds in organic chemistry. Their utility has already been demonstrated in various domains, including natural product synthesis, selective transformations, ring expansions, etc. However, only the basic chemistry of the electrophilic cyclopropanes has been unraveled and results originating from the application of new and modern selective reagents will certainly broaden the scope of its possibilities. 

The tandem zirconocene-induced co-cyclization of dienes or enynes/insertion of allyl carbenoid/addition of electrophile is a powerful method for assembling organic structures. Two illustrations of its application are the synthesis of the dollabelane natural product acetoxyodontoschismenol 99 [57,62,63] and the one-pot construction of linear terpenoids 100 (Scheme 3.25) [59,64],... 

Homophthahc anhydrides are very useful molecules in organic synthesis. Their 1,3-positions are electron-poor. They then react with nucleophiles at these positions. On the other hand, their 4-position is electron-rich, and electrophiles can react at the 4-position. Before our first use of homophthalic anhydrides in the cycloaddition reaction with a C - C multiple bond, many studies on their reactions with the C = O [1] or C = N [2] double bond and their applications to the syntheses of natural products and heterocyclic compounds [3-8] had been reported. However, no study on the cycloaddition of homophthalic anhydride with a C - C multiple bond, such as an olefin and acetylene, had been reported before our work. 

H. SYNTHESIS OF NATURAL PRODUCTS VIA Pd-CATALYZED CROSS-COUPLING INVOLVING a-HETERO-SUBSTITUTED ORGANIC ELECTROPHILES... 

The synthesis of aromatics and heteroaromatics is an important endeavor which, as for any class of organic materials, thrives on innovative strategies and economical methods to solve demanding problems in the construction of polysubstituted systems and complex molecules including natural products. From an indust perspective, tbe task is amply recognized from the ct that > 80% of today s commercial pharmaceuticals and agrochemicals embody aromatic or heteroaromatic components [7]. Aside from electrophilic substimtion, numerous methods, based on aromatics as well as non-... 

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