7731-02-4Relevant articles and documents
Bifunctional Behavior of Unsaturated Intramolecular Phosphane-Borane Frustrated Lewis Pairs Derived from Uncatalyzed 1,4-Hydrophosphination of a Dienylborane
Chen, Guo-Qiang,Kehr, Gerald,Daniliuc, Constantin G.,Wibbeling, Birgit,Erker, Gerhard
, p. 12449 - 12455 (2015)
Three unsaturated C4-bridged phospane/borane frustrated Lewis pairs (P/B FLPs) are prepared by uncatalyzed hydrophosphination of a dienylborane. The systems are bifunctional. Consequently, two examples undergo clean hydroboration reactions with
Formation of Thermally Robust Frustrated Lewis Pairs by Electrocyclic Ring Closure Reactions
Chen, Guo-Qiang,Kehr, Gerald,Daniliuc, Constantin G.,Mück-Lichtenfeld, Christian,Erker, Gerhard
, p. 5526 - 5530 (2016)
The phosphorus/boron-substituted hexatriene systems 6 undergo thermally induced electrocyclic ring closure to yield the cyclohexadiene-derived P/B frustrated Lewis pairs (FLPs) 7. Subsequent TEMPO oxidation gives the phenylene-bridged FLPs 8. Both systems activate dihydrogen and the thermally robust FLPs undergo carbon-carbon coupling reactions at a mesityl group upon treatment with dimethyl acetylenedicarboxylate at elevated temperatures.
Ni-Catalyzed reductive amination of phenols with ammonia or amines into cyclohexylamines
Cuypers, Thomas,Morias, Thomas,Windels, Simon,Marquez, Carlos,Van Goethem, Cédric,Vankelecom, Ivo,De Vos, Dirk E.
, p. 1884 - 1893 (2020/04/07)
Phenol and its derivatives, which naturally occur in lignocellulose, can be considered as a renewable feedstock not only for aromatic, but also for alicyclic compounds, such as primary and N-substituted cyclohexylamines. So far, the latter are mostly produced from non-renewable starting materials like benzene via problematic nitration/reduction or cross-coupling routes. Herein, an efficient reductive amination of phenol with ammonia or amines is demonstrated, for the first time without the need for rare and expensive noble metals and without using any additives. Various supported Ni catalysts were screened and we elucidated the influence of the key parameters, including the acid-base properties of the supporting material. Acquired knowledge was then applied to different phenol-ammonia/amine combinations, resulting in the synthesis of various primary, secondary and tertiary cyclohexylamines in fair to very high yields.
Ruthenium and Iron-Catalysed Decarboxylative N-alkylation of Cyclic Α-Amino Acids with Alcohols: Sustainable Routes to Pyrrolidine and Piperidine Derivatives
Afanasenko, Anastasiia,Hannah, Rachael,Yan, Tao,Elangovan, Saravanakumar,Barta, Katalin
, p. 3801 - 3807 (2019/07/31)
A modular and waste-free strategy for constructing N-substituted cyclic amines via decarboxylative N-alkylation of α-amino acids employing ruthenium- and iron-based catalysts is presented. The reported method allows the synthesis of a wide range of five- and six-membered N-alkylated heterocycles in moderate-to-excellent yields starting from predominantly proline and a broad range of benzyl alcohols, and primary and secondary aliphatic alcohols. Examples using pipecolic acid for the construction of piperidine derivatives, as well as the one-pot synthesis of α-amino nitriles, are also shown.
