A new class of α,β‐unsaturated δ‐oxacaprolactams was synthesized from imines as starting material. The synthetic procedure is based on an acyl chloride addition in the first step, followed by a ring‐closing metathesis using a ruthenium catalyst. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Abstract:The structure of the product of the Asinger reaction of acetophenone with n-butylamine and elemental sulfur is still under debate. Two products have been proposed: a hexathiocanthione containing a C 2 S 6 ring with an exocyclic thione and a heptathiocane containing a CS 7 ring. A single crystal X-ray study has shown that the heptathiocane structure is correct.1 H and 13 C NMR investigations in solution confirm that the structure is maintained in solution and that there is no evidence for the imine tautomer.

New classes of a,b-unsaturated caprolactams containing variable heteroatoms in d-position were synthesized from heterocyclic imines as a starting material. The synthetic route is based on an acid chloride addition followed by a ring-closing metathesis using a ruthenium catalyst.

The product of the Asinger reaction between elemental sulfur, n-butylamine and acetophenone is 8-(nbutylaminophenylmethyliden)-1,2,3,4,5,6,7-heptathiocane which contains a CS 7 ring. A combination of infrared, Raman and inelastic neutron scattering spectroscopies with periodic density functional theory calculations is used to provide a complete assignment of the vibrational spectra of this unusual species. The similarity between the Raman spectra of the compound and that of elemental sulfur is particularly striking.

First Synthesis of Bi-and Tricyclic α,β-Unsaturated δ-Oxacaprolactams from Cyclic Imines via Ring-Closing Metathesis. -The procedure is based on an acyl chloride addition in the first step, followed by ring-closing metathesis. The lactams are potentially bioactive due to their similarity to known and examined lactams. -(WATZKE, M.; SCHULZ, K.; JOHANNES, K.; ULLRICH, P.; MARTENS*, J.; Eur.

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Fused pyridine derivatives R 0450Synthesis of Bi-and Tricyclic α,β-Unsaturated Lactams as Potential Michael Acceptors Starting from Heterocyclic Imines. -Heterocyclic imines such as (I) are used as starting materials in the three-step synthesis of α,β-unsaturated valerolactams (VII) and (XI). The sequence involves an addition of acid chlorides followed by a modified Hosomi-Sakurai reaction and a final Ru-catalyzed ring closing metathesis. Lactam (VIIa) shows its potential as Michael acceptor in the reaction with thioacetic acid. -(SCHULZ, K.; WATZKE, M.; JOHANNES, K.; ULLRICH, P.; MARTENS*, J.; Synthesis 2009, 4, 665-673; Inst. Pure Appl. Chem., Carl v.

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