72340-40-0Relevant academic research and scientific papers
Enantiospecific Synthesis of Nepetalactones by One-Step Oxidative NHC Catalysis
Harnying, Wacharee,Neud?rfl, J?rg-M.,Berkessel, Albrecht
, p. 386 - 390 (2020/02/04)
An efficient oxidative NHC-catalyzed one-step transformation of (S)-or (R)-8-oxocitronellal to nepetalactone (NL) in enantio- A nd diastereomerically pure form has been developed. Several new and "easy to make" N-Mes-or N-Dipp-substituted 1,2,4-triazolium salts carrying nitroaromatic groups on N1 were synthesized and evaluated as precatalysts in combination with base and stoichiometric organic oxidant. Under optimized conditions, NLs are accessible in very good yields and diastereomerically pure under mild conditions. The oxidant used could be recovered and recycled under operationally simple conditions.
Multinuclear Cu(I) Clusters Featuring a New Triply Bridging Coordination Mode of Phosphaamidinate Ligands
Rathnayaka, Suresh C.,Lindeman, Sergey V.,Mankad, Neal P.
, p. 9439 - 9445 (2018/08/17)
Phosphabenzamidine [mes-NH-C(Ph)=P-mes) (1) and phosphaformamidine (mes-NH-CH=P-mes) (4) ligands have been synthesized and characterized. The conjugate bases of 1 and 4 coordinate by each bridging three Cu(I) ions, forming hexa- and tetranuclear clusters Cu6[mes-N=C(Ph)-P-mes]3Cl4Li(THF)2 (3) and Cu4[mes-N=CH-P-mes]4 (5), respectively. Both clusters have been fully characterized using 1H NMR, 31P NMR, and X-ray crystallography. Complexes 3 and 5 exhibit a previously unknown coordination mode of phosphaamidinates, which are far less studied than their well-known amidinate counterparts.
1,4-Bis-Dipp/Mes-1,2,4-Triazolylidenes: Carbene Catalysts That Efficiently Overcome Steric Hindrance in the Redox Esterification of α- And β-Substituted α,β-Enals
Yatham, Veera Reddy,Harnying, Wacharee,Kootz, Darius,Neud?rfl, J?rg-M.,Schl?rer, Nils E.,Berkessel, Albrecht
supporting information, p. 2670 - 2677 (2016/03/12)
As reported by Scheidt and Bode in 2005, sterically nonencumbered α,β-enals are readily converted to saturated esters in the presence of alcohols and N-heterocyclic carbene catalysts, e.g., benzimidazolylidenes or triazolylidenes. However, substituents at the α- or β-position of the α,β-enal substrate are typically not tolerated, thus severely limiting the substrate spectrum. On the basis of our earlier mechanistic studies, a set of N-Mes- or N-Dipp-substituted 1,2,4-triazolium salts were synthesized and evaluated as (pre)catalysts in the redox esterification of various α- or β-substituted enals. In particular the 1,4-bis-Mes/Dipp-1,2,4-triazolylidenes overcome the above limitations and efficiently catalyze the redox esterification of a whole series of α/β-substituted enals hitherto not amenable to NHC-catalyzed transformations. The synthetic value of 1,4-bis-Mes/Dipp-1,2,4-triazolylidenes is further demonstrated by the one-step bicyclization of 10-oxocitral to (racemic) nepetalactone in diastereomerically pure form.
Facile synthesis of phosphaamidines and phosphaamidinates using nitrilium ions as an imine synthon
Van Dijk, Tom,Burck, Sebastian,Rong, Mark K.,Rosenthal, Amos J.,Nieger, Martin,Slootweg, J. Chris,Lammertsma, Koop
, p. 9068 - 9071 (2014/10/15)
Readily accessible nitrilium triflates are convenient imine building blocks for the expedient synthesis of a novel class of 1,3-P,N ligands as demonstrated for the reaction with primary phosphanes. This procedure allows variation of all substituents. X-ray crystal structures are reported for nitrilium ions, phosphaamidines, and three phosphaamidinate complexes. The lithium phosphaamidinate is N coordinated and its reaction with [AuCl(tht)] (tht=tetrahydrothiophene) gives a unique P-bridged gold trimer, while a P,N-bidentate complex results from [{RhCl(cod)}2]. The nitrilium ion methodology allows extension of the 1,3-P,N motive to bis(imino)phosphanes, which are the neutral phosphorus analogues of the valuable β-diketiminate ligand.
Metal-free aminoamidiniumation employing N-iodosuccinimide: Facile syntheses of bicyclic imidazolidiniums and cyclic vicinal diamines
Zhang, Jun,Zhang, Gengtao,Wu, Weijie,Zhang, Xuejun,Shi, Min
, p. 15052 - 15054 (2014/12/11)
NIS-mediated aminoamidiniumation has been developed for the syntheses of bicyclic imidazolidinium salts, which could be readily converted into cyclic vicinal diamines.
SYNTHESIS OF SYMMETRICAL 1,2-DIHYDROTRIAZINES BY THE REACTION OF 1,1,1-TRIFLUORO-2-PHENYL-2,4,6,6-TETRACHLORO-3,5-DIAZAHEXA-3,5-DIENE WITH PRIMARY AMINES
Fetyukhin, V. N.,Vovk, M. V.
, p. 1001 - 1003 (2007/10/02)
The reaction of 1,1,1-trifluoro-2-phenyl-2,4,6,6-tetrachloro-3,5-diazahexa-3,5-diene with primary amines proceeds via two pathways and leads to 1,2-dihydro-1,3,5-triazines or the corresponding carbodiimides.The reaction pathway is determined by the steric
