Figure 1. X-ray crystal structure of trimethylammonium salt.
(TRIBS = triisopropylbenzenesulfonate)

	asdfadsfSulfonate groupda					Objective:    The development of an asymmetric reagent that relies upon an ion pair to control the stereochemical course and rate of a reaction. Significance:    The synthesis of pharmaceutical drugs and natural products depends upon efficient stereoselective synthetic methods. Many of today's asymmetric reagents use steric effects to achieve stereocontrol. The use of electrostatic fields is a new approach.
TRIBS				Trimethylammmonium group

Figure 2. 1,3-dipolar cycloaddition reaction.

Progress: 1) Early work with catalysis with and regioselectivity. (Ref 1,2) 2) Rational control of stereochemistry in cyclo-additions has been achieved. (Fig. 2, Ref 3) 1. Wilcox, C. S.; Smith, P. J. J. Org. Chem. 1990, 55, 5675-5678. 2. Wilcox, C. S.; Smith, P. J. Tetrahedron 1991, 47, 2617-2628. 3. Raposo, C.; C. S. Wilcox, C. S. "The Intramolecular Salt Effect in Chiral Auxiliaries. Enhanced diastereoselectivity in a nitrile oxide cycloaddition via rational transition state stabilization." Tetrahedron Lett. 1999, 1285-1288.

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