Synthesis of Cyclic Imines Having Conjugated Exocyclic Double Bond

Face selective reduction of the exocyclic double bond in isatin derived spirocyclic lactones.

We report an unusual face selective reduction of the exocyclic double bond in the α-methylene-γ-butyrolactone motif of spiro-oxindole systems. The spiro-oxindoles were assembled by an indium metal mediated Barbier-type reaction followed by an acid catalyzed lactonization.

Unique prototropy of meso-alkylidenyl carbaporphyrinoid possessing one meso-exocyclic double bond.

Generic synthesis, identification of structural identity, unique prototropy and spectroscopic properties of meso-alkylidenyl-thia(m-benzi)porphyrinoid containing one exocyclic double bond at the meso-position were presented.

One-step synthesis of diazaspiro[4.5]decane scaffolds with exocyclic double bonds.

Unactivated yne-en-ynes reacted with a range of substituted aryl halides in the presence of Pd(OAc)2-PPh3 to afford diazaspiro[4.5]decane with exocyclic double bonds. Three carbon-carbon bonds are formed in this domino reaction, which involves highly regioselective C-C coupling and spiro scaffold steps.

Metal-free catalytic hydrogenation of enamines, imines, and conjugated phosphinoalkenylboranes.

Synthesis and enantioselective hydrogenation of seven-membered cyclic imines: substituted dibenzo[b,f][1,4]oxazepines.

Highly enantioselective hydrogenation of seven-membered cyclic imines, substituted dibenzo[b,f][1,4]oxazepines, was achieved, with up to 94% ee, by using the [Ir(COD)Cl](2)/(S)-Xyl-C(3)*-TunePhos complex as the catalyst in the presence of morpholine-HCl.