Joel D. Moore

Ring-Closing Metathesis Strategies to Cyclic Sulfamide Peptidomimetics

Abstract Ring-closing metathesis (RCM) strategies toward the synthesis of a number of constrained sulfamides are discussed. This approach exploits the inherent chemistry of sulfamides and sulfonyl carbamates to generate both symmetric and unsymmetric cyclic sulfamides. Two strategies are revealed, one centers on the RCM reaction of allylated sulfamides 9a–e to generate the C2-symmetric cyclic sulfamides 4a–e in high yields. A second RCM strategy utilizes the known sulfonyl carbamate 15 to prepare unsymmetric cyclic sulfamides 16 and 6 in two four-step sequences. Overall, the routes described are applicable to the synthesis of a variety of constrained dipeptidal sulfamides representing novel peptidomimetic scaffolds.

A convenient approach to cyclic enol phosphates via ring-closing metathesis

A strategy employing the second generation Grubbs catalyst in order to facilitate the generation of a variety of cyclic enol phosphates, including 2H-chromen-4-yl, 1,2-dihydroquinolin-4-yl, 2H-thiochromen-4-yl, 2H-thiochromen-4-yl 1,1-dioxide, and benzofuran-2-yl enol phosphate scaffolds is described. This work represents the first case of an olefin metathesis reaction in which one of the groups participating in the metathesis event is an enol phosphate moiety.

Substituent effects in the double diastereotopic differentiation of α-diazophosphonates via intramolecular cyclopropanation

Abstract The investigation of substituent effects in the double diastereotopic differentiation of substituted α-diazophosphonates using intramolecular cyclopropanation catalyzed by Rh 2 (OAc) 4 is reported. Carbene facial selectivity in these transformations is dictated by substrate control in either of two ways: (i) exploitation of ( R ) - pantolactone as an auxiliary incorporated into the carboester functionality while probing olefinic substituent effects, or (ii) utilization of chiral, non-racemic allylic alcohols incorporated into the phosphonate moiety.

Diastereotopic Differentiation to P -Chiral Phosphonamides and Phosphonates

As part of our program aimed at developing transition metal-catalyzed approaches to diverse phosphorus-containing compounds, we herein report examples of utilizing the ring-closing metathesis reaction (RCM) in the diastereotopic differentiation of pseudo-C2-symmetric phosphonamide and phosphonate templates generating P-heterocycles 1 and 2. The RCM reaction continues to emerge as a powerful approach for the construction of complex organic molecules. Recently we have shown that the RCM reaction catalyzed by the Grubbs ruthenium catalyst is an effective method for the construction of phosphonate and phosphonamide P-heterocycles.1−3