Constrained Geometry Organoactinide Complexes: Scope and Mechanism of Intramolecular Hydroamination/Cyclization of Primary and Secondary Amines

Bryan D Stubbert
2006 unpublished
Constrained Geometry Organoactinide Complexes: Scope and Mechanism of Intramolecular Hydroamination/Cyclization of Primary and Secondary Amines Bryan D. Stubbert In Chapter 1, a series of "constrained geometry" organoactinide complexes, (CGC)An(NMe) 2 (CGC = Me 2 Si(η 5 -Me 4 C 5 )( t BuN); An = Th, 1; U, 2), prepared via efficient in situ, two-step protodeamination routes in good yields and high purity, is presented. Both 1 and 2 are quantitatively converted to the neutrally charged,
more » ... charged, solvent-free dihalides (1-Cl 2 , 2-Cl 2 and 1-I 2 , 2-I 2 ) with excess Me 3 Si-X (X = Cl, I) in non-coordinating solvents. Characterization of 1 and 2 by single crystal X-ray diffraction reveals substantially increased metal coordinative unsaturation vs. the corresponding Me 2 SiCp" 2 AnR 2 (Cp" = η 5 -Me 4 C 5 ; An = Th, R = CH 2 (SiMe 3 ), 3; An = U, R = CH 2 Ph, 4) and Cp' 2 AnR 2 (Cp' = η 5 -Me 5 C 5 ; An = Th, R = CH 2 (SiMe 3 ), 5; An = U, R = CH 2 (SiMe 3 ), 6) complexes. Complexes 1-6 exhibit broad applicability for the intramolecular hydroamination (HA) of diverse C-C unsaturations, including terminal and internal aminoalkenes (primary and secondary amines), aminoalkynes (primary and secondary amines), aminoallenes, and aminodienes. Large turnover frequencies (N t up to 3000 h -1 ) and high regioselectivities (≥ 95%) are observed throughout. With several noteworthy exceptions, reactivity trends track relative 5f ionic radii and ancillary ligand coordinative unsaturation. Reactivity patterns and activation parameters are consistent with a reaction pathway proceeding via turnover-limiting C=C/C≡C insertion into the An-N σ-bond. BIPmeister, the friendship that developed with Fred quickly became far more important than any other aspect of BIP, and I will always remember it fondly. My labmates and friends from the Marks group have also been instrumental in my research progress. From the day that Nikki Edelman greeted me in G Wing, the senior members of the group served as a collective student mentor as I tried to get my equipment and project up and running. In particular, I would like to thank Nikki, for their camaraderie, even after departure (theirs or my own). The other hydroelementation types -Douglass, Amber, Sukwon, Jaesang Ryu, Masataka Oishi, Jiuqing Zhao, Holming, Bruce Xianghua Yu -are owed a special thanks for making our marathon f-element meetings (and sub-subgroup as a whole) an interesting adventure that, at times, seemed to last forever. A special thanks to Tryg Jensen is also in order for acting as a mentor during my zero-year, but more so for being a friend and roommate. Along with Eli Sone,
doi:10.21985/n2kd8z fatcat:o3g5mm4rpvgarjj6p7fb5lq5u4