@article {https://doi.org/10.1002/chem.202100014, title = {Zirconium Catalyzed Hydroaminoalkylation for the Synthesis of α-Arylated Amines and N-Heterocycles}, journal = {Chemistry {\textendash} A European Journal}, volume = {27}, number = {20}, year = {2021}, pages = {6334-6339}, abstract = {Abstract The zirconium catalyzed hydroaminoalkylation of alkenes with N-aryl- and sterically demanding N-alkyl-α-arylated secondary amines by using commercially available Zr(NMe2)4 is reported. N-phenyl- and N-isopropylbenzylamine are used as amine substrates to establish the alkene substrate scope. Exclusively linear products are obtained in the presence of bulky vinylsilanes. Challenging α-heteroarylated amines and functionalized alkene substrates are compatible with this easy to use catalyst, affording a new disconnection strategy for the atom- and step-economic preparation of selectively substituted saturated α-arylated heterocycles.}, keywords = {alpha-arylated amines, HETEROCYCLES, HYDROAMINOALKYLATION, ZIRCONIUM}, doi = {https://doi.org/10.1002/chem.202100014}, url = {https://chemistry-europe.onlinelibrary.wiley.com/doi/abs/10.1002/chem.202100014}, author = {Koperniku, Ana and Schafer, Laurel L.} } @inbook {SCHAFER2020405, title = {Titanium catalyzed synthesis of amines and N-heterocycles}, booktitle = {Advances in Organometallic Chemistry}, volume = {74}, year = {2020}, pages = {405-468}, publisher = {Academic Press}, organization = {Academic Press}, abstract = {

Titanium is an earth abundant inexpensive early transition metal that has been used extensively in industrial polyolefin synthesis, but rarely applied toward the synthesis of fine chemicals. Recent advances have shown the usefulness of titanium catalyzed reactions in the catalytic synthesis of amines and N-heterocycles by both hydroamination and hydroaminoalkylation. These atom economic transformations can be coupled with other reactive bond insertion processes to realize catalytic multicomponent coupling reactions to generate more complex products. Alternatively, sequential catalytic protocols can be accomplished in one-pot to achieve efficient transformations, further emphasizing titanium catalysis as an under-utilized metal for Green Chemistry. Titanium also has multiple oxidation states that are accessible and have been featured in stoichiometric reactions over the past 40 years. More recently new strategies for taking advantage of oxidative addition/reductive elimination protocols and radical chemistry has resulted in new catalytic approaches. Throughout the highlighted work titanium offers complementary reactivity to established late transition metal protocols. However, ligand modified reactivity remains poorly understood and the development of predictive tools for understanding how ligands influence electronic properties at the metal center will advance efforts to realize new catalytic reactions. Furthermore, strategic ligand designs that control the steric environment about the titanium metal center to promote stereoselective transformations are desirable. Due to the extensive exploration of fundamental stoichiometric transformations with titanium complexes over the years, there are many attractive reactions that await creative insights for the realization of catalytic variants.

}, keywords = {Green chemistry, HYDROAMINATION, HYDROAMINOALKYLATION, Hydrofunctionalization, Multicomponent coupling, One-pot reactions, Redox-relay reactions, Reductive coupling}, issn = {0065-3055}, doi = {https://doi.org/10.1016/bs.adomc.2020.04.003}, url = {https://www.sciencedirect.com/science/article/pii/S0065305520300162}, author = {Laurel L. Schafer and Manfred Man{\ss}en and Peter M. Edwards and Erica K.J. Lui and Samuel E. Griffin and Christine R. Dunbar}, editor = {Pedro J. P{\'e}rez} } @article {31534, title = {Catalytic and Atom-Economic C -C Bond Formation: Alkyl Tantalum Ureates for Hydroaminoalkylation}, journal = {Angewandte Chemie International Edition}, volume = {57}, year = {2018}, pages = {3469-3472}, abstract = {

Abstract Atom-economic and regioselective C \−C bond formation has been achieved by rapid C\−H alkylation of unprotected secondary arylamines with unactivated alkenes. The combination of Ta(CH2SiMe3)3Cl2, and a ureate N,O-chelating-ligand salt gives catalytic systems prepared in situ that can realize high yields of β-alkylated aniline derivatives from either terminal or internal alkene substrates. These new catalyst systems realize C\−H alkylation in as little as one hour and for the first time a 1:1 stoichiometry of alkene and amine substrates results in high yielding syntheses of isolated amine products by simple filtration and concentration.

}, keywords = {AMINES, C-H activation, HYDROAMINOALKYLATION, tantalum alkyls, ureates}, doi = {10.1002/anie.201712668}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.201712668}, author = {DiPucchio, Rebecca C. and Ro{\c s}ca, Sorin-Claudiu and Schafer, Laurel L.} } @article {2363, title = {Selective C-H Activation alpha to Primary Amines. Bridging Metallaaziridines for Catalytic, Intramolecular alpha-Alkylation}, journal = {Journal of the American Chemical Society}, volume = {131}, number = {6}, year = {2009}, note = {ISI Document Delivery No.: 427PWTimes Cited: 22Cited Reference Count: 28Bexrud, Jason A. Eisenberger, Patrick Leitch, David C. Payne, Philippa R. Schafer, Laurel L.}, month = {Feb}, pages = {2116-+}, type = {Article}, abstract = {Selective alpha-C-H activation results in the synthesis of the first bridging metallaaziridine complex for the catalytic alpha-alkylation of primary amines. Reaction development led to the preparation of new Zr 2-pyridonate complexes for this useful transformation. No nitrogen protecting groups are required for this reaction, which is capable of assembling quaternary chiral centers a to nitrogen. Preliminary mechanistic investigations suggest bridging metallaaziridine species are the catalytically active intermediates for this alpha-functionalization reaction, while monomeric imido complexes furnish azepane hydroamination products.}, keywords = {ALKENES, ALKYNES, BOND ACTIVATION, COMPLEXES, GENERATION, HYDROAMINOALKYLATION, INTERMOLECULAR HYDROAMINATION, NITROGEN, REACTIVITY, UNACTIVATED OLEFINS}, isbn = {0002-7863}, url = {://000264792200038}, author = {Bexrud, J. A. and Eisenberger, P. and Leitch, D. C. and Payne, P. R. and Schafer, L. L.} } @article {2408, title = {Tantalum-Amidate Complexes for the Hydroaminoalkylation of Secondary Amines: Enhanced Substrate Scope and Enantioselective Chiral Amine Synthesis}, journal = {Angewandte Chemie-International Edition}, volume = {48}, number = {44}, year = {2009}, note = {ISI Document Delivery No.: 513DPTimes Cited: 9Cited Reference Count: 25Eisenberger, Patrick Ayinla, Rashidat O. Lauzon, Jean Michel P. Schafer, Latcrel L.}, pages = {8361-8365}, type = {Article}, keywords = {ALKENES, ALKYLATION, alpha, amidates, BOND, C-H ACTIVATION, CATALYSIS, CATALYTIC HYDROAMINOALKYLATION, enantioselectivity, homogeneous, HYDROAMINATION, HYDROAMINOALKYLATION, IMINE, LIGANDS, tantalum, UNACTIVATED OLEFINS}, isbn = {1433-7851}, url = {://000271302900038}, author = {Eisenberger, P. and Ayinla, R. O. and Lauzon, J. M. P. and Schafer, L. L.} }