Direct N-substituted N-thiocarboxyanhydride polymerization towards polypeptoids bearing unprotected carboxyl groups

n-cyclicizer groups

ATTEMPTED PREPARATION OF N-SUBSTITUTED DIPHENYLCYCLOPROPENEIMINE N-OXIDE

The reaction of diphenylcyclopropenone with several N-substituted hydroxylamine and primary amines are investigated. Most of these reactions led to ring opened or ring enlarged products, instead of the desired N-Oxide or imine. The reaction of cyclopropeneimine with peracid-another possible route to N-substituted cyclopropeneimine N-Oxide is studied. Most of the unexpected products are ide...

Ruthenium indenylidene complexes bearing N-alkyl/N-mesityl-substituted N-heterocyclic carbene ligands.

We report on the synthesis and characterization of second generation ruthenium indenylidene catalysts bearing unsymmetrical N-heterocyclic carbene (NHC) ligands denoted as RuCl2(3-phenyl-1-indenylidene)(1-mesityl-3-R-4,5-dihydroimidazol-2-ylidene)(PCy3), in which R is methyl 8a, octyl 8b or cyclohexyl 8c. The characterization of 8a-c was performed by NMR spectroscopy, elemental analysis, IR, HR...

Direct N-alkylation of unprotected amino acids with alcohols

N-alkyl amino acids find widespread application as highly valuable, renewable building blocks. However, traditional synthesis methodologies to obtain these suffer from serious limitations, providing a major challenge to develop sustainable alternatives. We report the first powerful catalytic strategy for the direct N-alkylation of unprotected α-amino acids with alcohols. This method is highly s...

Some properties of n-capable and n-perfect groups

In this article we introduce the notion of n-capable groups. It is shown that every group G admits a uniquely determined subgroup (〖Z^n)〗^* (G) which is a characteristic subgroup and lies in the n-centre subgroup of the group G. This is the smallest subgroup of G whose factor group is n-capable. Moreover, some properties of n-central extension will be studied.