ROMPgel TosMIC reagent

Barrett, A.G.M., Cramp, S.M., Hennessy, A.J. et al. (2001) Oxazole synthesis with minimal purification synthesis and application of a ROMPgel Tosmic reagent. Organic Letters, 3,271-273. 

Reactions of aromatic or heteroaromatic aldehydes 144 with a ROMPgel Tosmic reagent 143, available from the ring opening metathesis of 142, allowed the preparation of a small library of oxazoles 145 in high yields and with minimal purification <01OL271>. 

Polymer-supported TosMIC reagent 1612 has been described and employed in an oxazole synthesis involving minimal purification [1203]. ROMPgel TosMIC reagent 1612 was prepared from the corresponding polymeric formamide 1611 by dehydration with phosphoryl chloride in 100% yield. 1611 was obtained by ROM polymerization of 1610 in 100% yield [1203]. 

Many 5-aryl-l,3-oxazoles, bearing various functions at the aryl group, can be prepared in good yields of 68-90% and with high purities from aldehydes and ROMPgel TosMIC reagent 1612 they are purified only by filtration without any need for chromatography [1203]. This makes the method particularly well-suited for use in combinatorial chemistry. 

Later, Barrett created the term ROMPgel for linear polymers, which swell but do not dissolve in certain solvents because of solubility restrictions governed by the nature of the functional monomer used. Such ROMPgels were prepared with a variety of different functional groups including phosphines [3], allyl-boronates [25], a polymeric Tosmic reagent [26], naphthalenes, and biphenyls [27], alkylphosphonates [28], as well as anhydrides [29], some in a precipitation polymerization setup similar to the one described by our group. 

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