Complementary molecular reactivity and

Scheme 2.28 Complementary molecular reactivity and molecular recognition for library purification.

Parlow J. J. Flynn, D. L. Solution-Phase Parallel Synthesis of a Benzoxaz-inone Library Using Complementary Molecular Reactivity and Molecular Recognition (CMR/R) Purification Technology, Tetrahedron 1998,54,4013. 

Flynn DL, Crich JZ, Devraj RV, Hockerman SL, Parlow JJ, South MS, Woodard S, Chemical library purification strategies based on principles of complementary molecular reactivity and molecular recognition, J. Am. Chem. Soc., 119 4874 1881, 1997. 

Parlow JJ, Mischke DA, Woodard SS, Utility of complementary molecular reactivity and molecular recognition (CMR/R) technology and... 

Parlow, J.J., Mischke, D.A. and Woodward, S.S., Utility of complementary molecular reactivity and molecular recognition CMR/R) technology and polymer supported reagents in solution-phase synthesis of heterocyclic carboxamides, J. Org. Chem., 62 (1997) 5908-5919. 

The selected example by Flynn et al. [133] presented some purification strategies based on complementary molecular reactivity, molecular recognition, artificially imparted molecular recognition and solid support reaction quenching. All these concepts were exemplified by real applications and the first is reported in Figure 7.16. 

Flynn, D.L., Crich, J.Z., Devraj, R.V., Hockerman, S.L., Parlow, J.J., South, M.S. and Woodard, J. (1997) Chemical library purification strategies based on principles of complementary molecular reactivity... 

A template must serve different purposes (i) It organizes reaction partners in such h way that a desired product is formed that would not form as easily in the absence of the template or would be formed as a minor component in a mixture of several competing products. Thus, its first task is to control reactivity, (ii) In order to achieve this, the template needs to bind to the reaction partners. Molecular recognition is consequently a prerequisite for lemplated synthesis. Thus, the binding sites of the components must be complementary to each other, (iii) The control of reactivity and the recognition of the reaction partners imply that information is stored in the template and transferred to the product of (lie reaction. The third important aspect is thus information transfer. 

It has been our experience that 7s(r) and Vs(r) play different but complementary roles with respect to molecular reactivity [71,83-85], Vs(r) is effective for treating noncova-lent interactions, which are primarily electrostatic in nature [74,86-89], For instance, a variety of condensed-phase physical properties - boiling points, critical constants, heats of phase transitions, solubilities and solvation energies, partition coefficients, surface tensions, viscosities, diffusion constants and densities - can be expressed quantitatively in terms of one or more key features of Vs(r), such as its maximum and minimum, average deviation, positive and negative variances, etc. [80,90-92], Hydrogen bond donating... 

The theory of molecular interactions, and the theory of chemical reactivity in particular, deal with reactive systems consisting of complementary subsystems. One of major goals of the quantum chemistry is to determine various effects of their interaction, both intra- and inter-subsystem in cheu acter, emd how they influence the ultimate reactivity trends. This can be studied, e.g., using the semi-empirically parametrized CSA in the atomic resolution. Its first-principle, local formulation in DFT... 

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