Contrasting connectivity of amidine and phosphaamidine (1,3-P,N) Cu(I) complexes
摘要:
Aprotic acetamidine {Me2N-C(Me)=N(R)(CuBr)}(2) {R = Pr-i (2a), Cy (2b), Ph (2c)} and neutral 1,3-P,N phosphaamidine copper bromide complexes {(CuBr)(Ph2PC(Ph)=NPh)}(4) (6a), {(CuBr)(4)(Ph2PC(Ph)=(NPr)-Pr-i)(2)}. {2CH(2)Cl(2)} (6b), (CuBr)(4)((Pr2PC)-Pr-i(Ph)=Ph)(2)} (7a) and {(CuBr)(4)((Pr2PC)-Pr-i(Ph)=(NPr)-Pr-i)(2)} (7b) are prepared by direct combination of corresponding amidine and phosphaamidine with CuBr(DMS). X-ray crystallographic analysis of the acetamidine complexes reveal monodentate N-imine coordination to copper with significant degree of delocalization about the N-C=N framework and a relatively short Cu-Cu interaction of 2.5758(8) angstrom in 2c compared to (2.9801)(10) angstrom 2a. The phosphaamidine ligands are never eta(1)-N-imine bound; instead they are eta(1)-P bound in the cubane complex 6a or eta(2)-bound in the step cluster complexes 6b, 7a and 7b. (C) 2016 Elsevier B.V. All rights reserved.
Contrasting Reactivity of CS<sub>2</sub>with Cyclic vs. Acyclic Amidines
作者:M. Trisha C. Ang、Lam Phan、Aliyah K. Alshamrani、Jitendra R. Harjani、Ruiyao Wang、Gabriele Schatte、Nicholas J. Mosey、Philip G. Jessop
DOI:10.1002/ejoc.201500973
日期:2015.11
to give an isothiocyanate and a thioacetamide. Because the pathway to that cleavage involves a rotation that is difficult for cyclic amidines, the reaction of CS2 with cyclic amidines produces an entirely different product: a cyclic carbamic carboxylic trithioanhydride structure. The path to that product involves sp3 C-H activation leading to the formation of a new C–C bond at a carbon α to the central