Letter pubs.acs.org/OrgLett
Copper-Catalyzed Chan−Lam Coupling between Sulfonyl Azides and Boronic Acids at Room Temperature Soo-Yeon Moon, Jungsoo Nam, Kris Rathwell, and Won-Suk Kim* Department of Chemistry and Nano Science, Ewha Womans University, Global Top 5 Program, Seoul 120-750, Korea S Supporting Information *
ABSTRACT: A mild and efficient method for the synthesis of N-arylsulfonamides in the presence of 10 mol % of CuCl is demonstrated. The reaction proceeds readily at room temperature in an open flask using a variety of sulfonyl azides and boronic acids without any base, ligand, or additive.
Table 1. Optimization of the N-Arylation Reaction of Phenylboronic Acid 1a with Tosyl Azide 2a
N-Arylsulfonamides are a common moiety present in a large number of pharmaceutically interesting compounds (Figure
Figure 1. N-Arylsulfonamide-containing drugs.
Scheme 1. Synthesis of N-Arylsulfonamides
entry
Cu cat.
solvent
time (h)
yieldb (%)
1 2 3 4 5 6 7 8 9 10 11 12 13
Cu(OAc)2 CuO CuCl2 Cul CuBr Cu2O CuBr S(Me)2 CuCl CuClc CuCld none CuCl CuCl
MeOH MeOH MeOH MeOH MeOH MeOH MeOH MeOH MeOH MeOH MeOH THF CH2Cl2
3 24 24 24 3 24 2 1 1 1 24 24 24
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