Although Cp*Rh(III) complexes are prominent and versatile catalysts for C-H bond functionalization reactions, catalytic stereocontrol is difficult due to the lack of vacant coordination sites. Here we report a hybrid strategy for inducing chirality without using previously reported chiral Cp x ligands. A preformed hybrid catalyst, [Cp*RhL N ][6,6'-Br-(S)-BINSate], catalyzed C-H activation and subsequent conjugate addition of 2-phenylpyridine derivatives to enones in good yield and enantioselectivity (up to 95:5 er). In addition to 2-phenylpyridines, conjugate addition of 6-arylpurines proceeded in up to 91:9 er using [Cp*RhL N ][(R)-SPISate]. The results demonstrated that a chiral organic anion can efficiently control the enantioselectivity of Cp*Rh(III)-catalyzed C-H bond functionalization without a chiral Cp x ligand. Transition metal catalysts cleave inert carbon-hydrogen (C-H) bonds in organic molecules to form reactive organometallic intermediates, enabling catalytic transformation of C-H bonds to desired carbon-carbon and carbon-heteroatom bonds. This catalytic C-H bond functionalization strategy can facilitate the development of atom-1 and step-economical 2 syntheses of functional molecules, and thus has been intensively investigated over the several decades. 3-16 Among various types of transition metal catalysts studied for catalytic C-H bond functionalization, Rh(III) complexes bearing a pentamethylcyclopentadienyl (Cp*) or related cyclopentadienyl-type (Cp,

Inter- and intramolecular additions of alkyl radicals, generated by SET photochemical decarboxylation reactions of free carboxylic acids, to electron-deficient alkenes take place under mild conditions as part of efficient routes for the formation of N-Boc gamma-amino acids and macrocyclic lactones.

A phasic increase in activity similar to that of acidic fibroblast growth factor (aFGF) was detected in the cerebrospinal fluid of rats after feeding or after an intraperitoneal injection of glucose. This FGF-like activity in the cerebrospinal fluid was bioassayed in two systems: depression of the feeding response of Hydra and DNA synthesis-stimulating activity in BALB/c 3T3 cells after fractionation on a heparin affinity column. Dynamic feeding-related changes in activity of aFGF, basic FGF, and other growth factors were detected by both bioassay systems. Intracerebroventricular microinfusion of aFGF suppressed food intake in rats. Central infusion of inactivated aFGF, or peripheral administration of aFGF, in doses equivalent to or higher than those administered centrally was without effect. Electrophoretically applied aFGF specifically suppressed the activity of glucose-sensitive neurons in the lateral hypothalamus. Glucose-insensitive neurons were only slightly affected. The results suggest that aFGF may participate in the regulation of feeding at the level of the central nervous system.

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The first asymmetric total synthesis of (-)-stemonamine is described. The key reactions included intramolecular acylation to construct the seven-membered ring and a tandem [2+2] cycloaddition-Dieckmann condensation reaction using an ynolate to form the fully substituted cyclopentenone moiety. Racemization and epimerization of the natural product were first experimentally demonstrated.