Pyrrolidine synthesis via palladium-catalyzed trimethylenemethane cycloaddition and related studies

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1992

OSTI ID:7235701

Marrs, C M

The palladium catalyzed trimethylenemethane cycloaddition has been extended to the synthesis of pyrrolidines and azepines. In contrast to previous attempts with N-alkyl and N-aryl imine, successful cycloadditions were recorded with several aromatic and aliphatic electron-deficient imines. Sulfonimines were found to be excellent acceptors, yielding pyrrolidine cycloadducts in excellent yields. Aromatic sulfonimines were observed to undergo cycloaddition very rapidly at or below room temperature. Some aliphatic nitrimine and N-phenyl, C-carbalkoxy imines were also found to be useful acceptors. Azepines were obtained from the cycloaddition of cisoid lockeed [alpha],[beta] unsaturated sulfonimines. In order to support the cycloaddition studies, a novel synthetic method was developed for the synthesis of sulfonimines. bis(Toluene-sulfonylimido)tellurium, Te(=N-Ts)[sub 2], generated from tellurium metal and anhydrous chloramine-t, was found to convert both aromatic and aliphatic aldehydes into the corresponding sulfonimines. Chiral ligands were examined in this cyclization and an enantiomeric excess of 35% was achieved with Hayashi's bidentate ferrocenyl ligand (BPFA). In support of this effort, the total synthesis of [+-] nicotine was accomplished in seven steps starting from pyridine 3-carboxaldehyde using these methodologies in order to verify the enantiomeric excess. Finally, the trimethylenemethane cycloaddition was examined with tropone irontricarbonyl complex. A novel [5+3] cycloaddition was observed to proceed in good yield, which upon decomplexation from the iron tricarbonyl moiety yielded the tricyclo[3.2.0] system. The scope and generality were briefly examined. Extended Huekel calculations were performed in order to help rationalize the unexpected regiochemistry.

• Research Organization: Stanford Univ., CA (United States)
• OSTI ID: 7235701
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
AMINES
AZOLES
CATALYTIC EFFECTS
CHEMICAL PREPARATION
CHEMICAL REACTIONS
COMPLEXES
ELEMENTS
HETEROCYCLIC COMPOUNDS
IMINES
IRON COMPLEXES
METALS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PALLADIUM
PLATINUM METALS
PYRROLES
PYRROLIDINES
SYNTHESIS
TELLURIUM COMPLEXES
TRANSITION ELEMENT COMPLEXES
TRANSITION ELEMENTS