Fragmentable electron donor compounds with broad blue spectral sensitization

This invention comprises a photographic element comprising a support and at least one blue sensitive silver halide emulsion layer containing a tabular grain silver halide emulsion, or an emulsion in which the halide content is at least 50% chloride and no more than 5% iodide, wherein the emulsion is spectrally sensitized with at least one dye providing a peak sensitization between 446 and 500 nm and at least one dye providing a peak sensitization between 400 and 445 nm and additionally sensitized with a fragmentable electron donor of the formula: X-Y'. or an electron donor which contains an -XY' moiety; wherein X is an electron donor moiety, Y' is a leaving proton H or a leaving group Y, with the proviso that if Y' is H a base, beta , is covalently linked directly or indirectly to X. and wherein: 1) X-Y' has an oxidation potential between 0 and about 1.4 V; and 2) the oxidized form of X-Y' fragments to give the radical X and the leaving fragment Y'; and, optionally, 3) the radical X has an oxidation potential ≤-0.7V (that is, equal to or more negative than about -0.7V).