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[reaction: see text] Two strategies for preparing catalytically active molecularly imprinted nitroxide-containing polymers are outlined. Both strategies rely upon the thermal rearrangement chemistry of tertiary amine N-oxides. To this end, several polymers were prepared and the polymeric nitroxides were revealed by oxidation with m-CPBA. All of the resulting polymeric catalysts proved to be competent mediators of the oxidation of alcohols.

[reaction: see text] The alcohol-catalyzed Diels-Alder reactions of acrolein and benzaldehyde with Rawal's diene were evaluated with density functional theory (B3LYP/6-31G(d)). Several potential modes of catalysis with two methanol molecules were used to model catalysis by TADDOLs. In agreement with crystallographic data, cooperative catalysis with TADDOLs is predicted to be favorable.

The synthesis and absolute configuration of SCH 351448, an interesting ionophoric natural product, are reported herein. Mukaiyama aldol-Prins and segment-coupling Prins reactions were employed to construct the constituent tetrahydropyrans of SCH 351448. Efforts to assemble the C2-symmetric core of the natural product by a templated olefin metathesis strategy are described, however, a stepwise fragment assembly was ultimately utilized to complete the target molecule.

The asymmetric hetero-Diels-Alder reaction of benzaldehyde with 1-dimethylamino-3- tert-butyldimethylsiloxy butadiene catalyzed by ( R, R)-1-Np-TADDOL was studied using computational methods. A theoretical rationale was developed through the combined use of molecular mechanics and ONIOM(B3LYP/6-31G(d):AM1) calculations. The origins of stereoselection in this process were identified, and excellent correlation between experiment and theory was found.

[Structure: see text] OH...OH hydrogen bond mediated scalar couplings have been observed in acyclic syn- and anti-1,3-diols using a 2D 1H COSYLR NMR experiment and quantified with an uncertainty of +/-0.02 Hz with a selective-excitation spin-echo NMR experiment. A theoretical investigation confirmed the importance of the hydrogen bond in mediating the spin-spin coupling in these systems.

[chemical reaction: see text]. Using an operationally simple deuterium isotopic perturbation method, the relative configuration of 1,3-diols can be determined directly using 1H NMR spectroscopy. A comparison of the OH chemical shifts for OH/OH and OH/OD isotopomers provides a reliable assessment of the relative configuration of the diol; anti-1,3-diols within polyacetate and polypropionate frameworks have upfield isotope shifts of 2-16 ppb, whereas syn-1,3-diols show upfield isotope shifts of 20-33 ppb.

[structure: see text] A useful method for the prediction of molar rotation ([Phi]) of syn-2,2-dimethyl-1,3-dioxanes (acetonides) is described. A series of acetonides were prepared by standard methods. A simple additive relationship between the substituents (R, R') and molar rotation was realized.