Angewandte Chemie Communications Scheme 2. Synthesis and fluorination of aryl sulfonium salts. TTO = thianthrene S-oxide;D BTO = dibenzothiophene S-oxide;B-DBTO = 3,7di-tert-butyldibenzothiophene S-oxide;M -DBTO = 2,8-dimethoxydibenzothiophene S-oxide. Angewandte Chemie Communications

Radiolabeled receptor-binding peptides are an important class of positron emission tomography tracers owing to achievable high binding affinities and their rapid blood clearance. Herein, a method to introduce a 4-[ F]fluoro-phenylalanine residue into peptide sequences is reported, by chemoselective radio-deoxyfluorination of a tyrosine residue using a traceless activating group. The replacement of only one hydrogen atom with [ F]fluoride results in minimal structural perturbation of the peptide, which is desirable in the labeling of tracer candidates.

Key building blocks for the production of fully synthetic macrolides have been scaled-up in first time pilot plant and kilo-lab campaigns. These building blocks have supported the discovery of new macrolide antibiotics as well as ongoing preclinical studies.

Site‐selective functionalization of C−H bonds in small complex molecules is a long‐standing challenge in organic chemistry. Herein, we report a broadly applicable and site‐selective aromatic C−H dibenzothiophenylation reaction. The conceptual advantage of this transformation is further demonstrated through the two‐step C−H [18F]fluorination of a series of marketed small‐molecule drugs.

Here we describe the realization of a one-pot protocol for the β-C-H halogenation of cyclic enones via umpolung of the β-carbon. The developed method includes hydrazone formation and selective β-halogenation (bromination, chlorination) with N-bromosuccinimide and Palau'chlor (2-chloro-1,3-bis(methoxycarbonyl)guanidine) followed by hydrolysis of the hydrazone moiety. Using the optimized conditions, we were able to effectively β-brominate and β-chlorinate for the first time cyclic enones with different substitution patterns and various functional groups in one flask, whereas previous methods for this transformation required several steps. Additionally, the utility of the method was demonstrated in a short synthesis of the core structure of the Aspidosperma alkaloid jerantinine E.