States in Facioselective Processes

The reaction at a paired set of molecular faces, in principle, may proceed through four pathways, or a quartet of conjunctive transition states (or four conjunctive products) mj, mj, m2, my. Thus, the analysis of these pathways centers cn the maximum level of structural complexity attainable - that of the incipient transition states - along the pathways. Each conjunctive state (transition state or product) is chiral (dark circle) or achiral (open circle). 

We have systematically analyzed the outcome of a wide variety of (l,2)-atom-face and (2,2)-bond-face ligogenic reactions of prototype alkenes, belonging to the eleven fundamental subclasses, with monojimctive/bijunctive C2-symmetric/non-C2-symmetric, achiral/chiral reagents of general types Cab, C=Cxy, C=C=Cxy, and x-y, (x=y and x ty x,y= achiral or chiral ligands). We have also examined (2,2)-face-face ligogenic processes based on [2+2] and [2+4] cycloadditions - those involving reactants of types xyC=Cwz and xyC=Ca-Cb=Cwz. 

O achiral conjunctive state chiral conjunctive state 

For the example above, facioselectivity would be given by either Equation 12.1a (as a difference) or Equation 12.1b (as a ratio)  

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