Uranyl nitrate as a recyclable homogeneous photocatalyst for selective cross-coupling of N-substituted amines and indoles

Abstract

A homogeneous photocatalytic recyclable system for the selective radical–radical cross-coupling of N-substituted amines and indoles has been established.

Ligand control of hydrocarbon C-H bond functionalization by uranyl photocatalysts

“…9 In recent years, a rapidly growing range of substrate oxidations are being reported for uranyl nitrate hexahydrate, such as the addition of (cyclo)alkanes to electron-poor olefins, ethers, acetals, and amides arising from hydrogen atom abstraction (HAA) from the hydrocarbon substrate, and other ether and sulfone oxidations. [10][11][12][13][14][15][16][17][18] Uranyl acetate, uranyl sulfate UO2SO4•4H2O, and uranyl triflate UO2(OTf)2•6H2O were all found to give lower yields than uranyl nitrate in those reactions. 6,7,9,18 Uranyl chemistry is dominated by fast ligand exchange between the (normally) five ligands bound in the equatorial plane.…”

The effect of ancillary ligands on hydrocarbon C–H bond functionalization by uranyl photocatalysts

“…9 A rapidly growing range of substrate oxidations is now being reported for uranyl nitrate hexahydrate, include the addition of (cyclo)alkanes to electronpoor olens, ethers, acetals, and amides arising from HAT from the hydrocarbon substrate, ether, sulfone, aniline oxidations, and polymer degradation. [10][11][12][13][14][15][16][17][18][19][20] Uranyl acetate, uranyl sulfate UO 2 SO 4 $4H 2 O, and uranyl triate UO 2 (OTf) 2 $6H 2 O were all found to give lower yields than uranyl nitrate in those reactions. 6,7,9,18 Uranyl chemistry is dominated by fast ligand exchange between the (normally) ve ligands bound in the equatorial plane.…”

Towards tailoring hydrophobic interaction with uranyl(vi) oxygen for C–H activation

“…15 Ligand coordination apparently downgrades the oxidizing power of [UO 2 2+ ]*. On the other hand, several coordination complexes of uranyl are reported to be photoreactive, such as nitrates, 9,17,18 [UO 2 (NO 3 ) 2 (Ph 2 phen)], 19 and [UO 2 (OPMe 3 ) 4 ] 2+ . 20 We have also recently discovered that photoexcited [UO 2 (CO 3 ) 3 ] 4− , which has significantly weaker oxidizing power than photoexcited [UO 2 (H 2 O) 5 ] 2+ , is capable of abstracting H from BH 4 − .…”