Nazarov Reactions of Vinyl Cyclopropylamines: An Approach to the Imino-Nazarov Problem
摘要:
Dichlorocyclopropanation of 2-amino-1,3-dienes affords 1-alkenyl-1-amino-2,2-dichlorocyclopropanes which undergo silver-assisted 2-pi electrocyclic opening to furnish 3-aminopentadienyl cations. Nazarov-type cyclization of these intermediates leads to cyclopentenone iminium salts, which provide allylic amines upon reduction. This process, the imino version of the traditional Nazarov reaction, can also be combined with an interrupted Nazarov domino process to give polycyclic amines.
Under specific reaction conditions only the terminal Ctriple bond of several alk-3-en-1-ynes adds amines, viacatalyticaminomercuriation, to afford 1-aza- and 2-morpholino-1,3-dienes.
2-Morpholinobutadienes have been found to show different behaviour in the reaction with isocyanates and isothiocyanates. While isocyanates give rise always to openchain compounds, isothiocyanates yield mainly thiin1 derivatives.
Stereospecific [4+2] Reaction between 2-Morpholino-1,3-butadienes and α,β-Unsaturated Exocyclic Chromium Carbene Complexes. Preparation of Enantiomerically Pure Spiro Compounds
A stereospecific exoselective [4+2] reaction between α,β-unsaturated exocyclic chromium carbene complexes and 2-amino-1,3-butadienes is described. Its application employing homochiral carbene complexes gives rise to the optically pure spiro-lactones.
Tandem Cycloaddition-Cyclopentannulation Processes of 2-Aminobuta-1,3-dienes and Fischer Alkynylcarbene Complexes as a Tool for the Preparation of Complex Polycyclic Scaffolds
This letter describes a convenient one-pot four-step cascade reaction of 2-aminodienes and vinyl substituted alkynyl carbene complexes that produces complex polycyclic molecules in a stereoselective manner.
A polymer includes the polymerized product of monomers including a nitrogen-containing monomer comprising formula (Ia), formula (Ib), or a combination of formulas (Ia) and (Ib), and an acid-deprotectable monomer having the formula (II):
wherein a, L
1
, LN, R
a
, R
b
, R
c
, and X are defined herein. The polymer is a useful component of a photoresist composition.