A stable dirhodium tetracarboxylate carbenoid: crystal structure, bonding analysis, and catalysis.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to T Stengel.
Explore the source record for details and available documents.
The regiospecific introduction of substituents into the 4-position of 2,3-dihydroindoles (indolines), which is significant for the synthesis of various natural products and pharmaceuticals, was achieved by rhodium(I)-catalyzed cyclotrimerizations of 1 with acetylene to give 2. Up to four substituents can be introduced simultaneously into the indoline core by using this novel strategy. R=OH, OBzl, Otetrahydropyranyl, NHSO(2)C(6)H(4)CH(3); Ts=H(3)CC(6)H(4)SO(2).
In Experiment 1 (within subjects) and Experiment 2 (between subjects) it was shown that the sequential training of pigeons on a color discrimination and then on its reversal, each in a different floor-tilt/texture context, failed to produce conditional control of discriminative performance by those contexts. Daily alternation between the two problems (with correlated contexts) was successful, however. In each of these experiments conditional control was better reflected in generalization test performance in extinction than during sessions of training with reinforcement.