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We report a metal-free radical perfluoroalkylation method which uses inexpensive and commercially available perfluorocarboxylic anhydrides as an easy to use source of perfluoroalkyl radicals. This approach allows the perfluoroalkylation of different arenes, such as benzene derivatives, furans, thiophenes, and pyrroles, including highly functionalized compounds.

Additional file 1. NMR-spectra of pNO2PheDU (4a) and NCarbpNO2 βPhe (5a).

We developed an asymmetric organocatalytic synthesis of 4{,}6-bis(1H-indole-3-yl)-piperidine-2-carboxylates using 10 mol% of a chiral phosphoric acid. The products{,} which are novel bisindole-piperidine-amino acid hybrids{,} can be obtained in one step from 3-vinyl indoles with imino esters in dichloromethane at room temperature after 1 h of reaction time. A variety of these compounds could be synthesized in up to 70% yield and 99% ee{,} and they were experimentally and computationally analyzed regarding their relative and absolute stereochemistry.

A novel substrate, 6-(4-nitrophenyl)dihydropyrimidine-2,4(1H,3H)-dione (pNO2PheDU), was chemically synthesized and analytically verified for the potential biocatalytic synthesis of enantiopure β-amino acids. The hydantoinase (EC 3.5.2.2) from Arthrobacter crystallopoietes DSM20117 was chosen to prove the enzymatic hydrolysis of this substrate, since previous investigations showed activities of this enzyme toward 6-monosubstituted dihydrouracils. Whole cell biotransformations with recombinant Escherichia coli expressing the hydantoinase showed degradation of pNO2PheDU. Additionally, the corresponding N-carbamoyl-β-amino acid (NCarbpNO2βPhe) was chemically synthesized, an HPLC-method with chiral stationary phases for detection of this product was established and thus (S)-enantioselectivity toward pNO2PheDU has been shown. Consequently this novel substrate is a potential precursor for the enantiopure β-amino acid para-nitro-β-phenylalanine (pNO2βPhe). Electronic supplementary material The online version of this article (doi:10.1186/s13568-015-0174-8) contains supplementary material, which is available to authorized users.