ChemInform Abstract: C‐Aminoimidoylation and C‐Thiocarbamoylation of Esters, Sulfones, and Ketones.

Abstract

Substitution reactions O 0040C-Aminoimidoylation and C-Thiocarbamoylation of Esters, Sulfones, and Ketones. -The reactions allow new and easy access to functionalized amidines and thioamides. Some amidines exist in form of their enamine tautomers. Interestingly, coupling of the N-benzylated thiourea derivative (VI) with ketones does not yield the corresponding thioamides but oxazolinethiones like (VII) or (IX). -(KATRITZKY*, A. R.; KHASHAB, N. M.; HAASE, D. N.; YOSHIOKA, M.; GHIVIRIGA, I.; STEEL, P.

Microwave‐Assisted Solid‐Phase Peptide Synthesis Utilizing N‐Fmoc‐Protected (α‐aminoacyl)benzotriazoles

“…N ‐Fmoc‐protected( α ‐aminoacyl)benzotriazoles 2a–g were prepared in 72–90% yield from the reaction of N α ‐Fmoc‐protected amino acids 1a–g (purchased from Peptides International, Louisville, KY, USA and used without further purification) with 4 equivalents of 1 H ‐benzotriazole and 1 equivalent of SOCl 2 in THF at 20 °C for 2 h following our published procedure (the reaction time for the complete conversion of Fmoc‐ L ‐Ala‐OH to Fmoc‐ L ‐Ala‐Bt 2a was 18 h in the presence of 2.5 equivalents of SOCl 2 ) (Scheme 1, Table 1) (5,9,19). The original chirality was preserved in all cases (>95% as evidenced by NMR), and the benzotriazole derivatives 2a–g are moisture insensitive and easy to handle.…”