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D. Enders, M.R.M. Hüttl, O. Niemeier
tandem reactions that may occur during biosyntheses of complex natural products. In nature, the coenzyme thiamin (vitamin B 1 ), a natural thiazolium salt,
is used in biochemical nucleophilic acylations (‘Umpolung’). The catalytic active species is a nucleophilic carbene. Mimicking this approach, organocatalytic
carbene catalysis has emerged to an exceptionally fruitful research area, which
is used in asymmetric C–C bond formations.
1
Introduction
The development and application of biomimetic strategies plays an
outstanding role in the synthesis of complex organic molecules from
simple precursors. In recent years these strategies have been used successfully in organic synthesis, but the development of synthetic equivalents of the naturally occurring building blocks is an ongoing challenge
in asymmetric biomimetic synthesis. Our group has already
developed some stereoselective methods using dihydroxyacetone phosphate (DHAP) or phosphoenol pyruvate (PEP) equivalents in combination with the SAMP/RAMP hydrazone methodology. With the
exploration of organocatalysis as a powerful tool of asymmetric catalysis, new biomimetic protocols come within reach, where small chiral
organic molecules act as catalytic active species mimicking the activation pathways of enzymes. These organocatalysts are metal free, usually non-toxic, readily available and often very robust. A significant
advantage of many organocatalysts is the capability of promoting reactions via different activation modes. In this chapter we report our recent
results in the development of methods for biomimetic organocatalytic
C–C-bond formations and their applications in the asymmetric synthesis of natural products and bioactive compounds in general.
D. Enders, M.R.M. Hüttl, O. Niemeier
tandem reactions that may occur during biosyntheses of complex natural products. In nature, the coenzyme thiamin (vitamin B 1 ), a natural thiazolium salt,
is used in biochemical nucleophilic acylations (‘Umpolung’). The catalytic active species is a nucleophilic carbene. Mimicking this approach, organocatalytic
carbene catalysis has emerged to an exceptionally fruitful research area, which
is used in asymmetric C–C bond formations.
1
Introduction
The development and application of biomimetic strategies plays an
outstanding role in the synthesis of complex organic molecules from
simple precursors. In recent years these strategies have been used successfully in organic synthesis, but the development of synthetic equivalents of the naturally occurring building blocks is an ongoing challenge
in asymmetric biomimetic synthesis. Our group has already
developed some stereoselective methods using dihydroxyacetone phosphate (DHAP) or phosphoenol pyruvate (PEP) equivalents in combination with the SAMP/RAMP hydrazone methodology. With the
exploration of organocatalysis as a powerful tool of asymmetric catalysis, new biomimetic protocols come within reach, where small chiral
organic molecules act as catalytic active species mimicking the activation pathways of enzymes. These organocatalysts are metal free, usually non-toxic, readily available and often very robust. A significant
advantage of many organocatalysts is the capability of promoting reactions via different activation modes. In this chapter we report our recent
results in the development of methods for biomimetic organocatalytic
C–C-bond formations and their applications in the asymmetric synthesis of natural products and bioactive compounds in general.