Synthesis of 1,4-epimine compounds. Iodosobenzene diacetate, an efficient reagent for neutral nitrogen radical generation

Complementary Strategies for Directed C(sp3)−H Functionalization: A Comparison of Transition‐Metal‐Catalyzed Activation, Hydrogen Atom Transfer, and Carbene/Nitrene Transfer

“…This obviates the handling of unstable nitrogen-halogen bonds.W ith the Suarez modification, elemental halogens,along with Pb(OAc) 4 or PhI(OAc) 2 , are used to generate an itrogen-halogen bond from aN ÀH bond. [115] Thep resence of an electron-withdrawing group (nitro,c yano,p hosphonyl, and carbonyl groups) on the nitrogen atom makes the nitrogen radical reactive enough to realize HAT. Thus,a mine derivative 216 bearing various electron-withdrawing groups is acompetent substrate for the HLF reaction.…”

Triiodide‐Mediated δ‐Amination of Secondary C−H Bonds

“…11 In this improved approach, generation of the N-centered radical is facilitated by direct oxidation of an amine with Hg(OAc) 2 or PhI(OAc) 2 . Additionally, use of an electron-deficient nitrogen substituent replaces the need for strongly acidic conditions by promoting 1,5-HAT via a polarized aminyl radical intermediate.…”

“…[2] Amajor milestone in the development of HLF chemistry is adiscovery by Suµrez and co-workers,and it precludes the need for haloamine pre-formation ( Figure 1b). [11] In this improved approach, generation of the N-centered radical is facilitated by direct oxidation of an amine with Hg(OAc) 2 or PhI(OAc) 2 .A dditionally,u se of an electron-deficient nitrogen substituent replaces the need for strongly acidic conditions by promoting 1,5-HATb yapolarized aminyl radical intermediate.T his modification enables CÀHf unctionalization [12] of previously inaccessible,a cid-sensitive molecules (e.g. carbohydrates).…”

“…Having successfully developed ap rotocol for the d-amination of unbiased, secondary CÀHb onds,w ea pplied this triiodide strategy to the cyclization of aw ide range of amines bearing medicinally relevant functionalities.A si llustrated in Table 2, the d-functionalization of secondary CÀH bonds is efficient and synthetically tractable by this triiodide strategy.N otably,s elective functionalization of unactivated, secondary C(sp 3 ) À Hb onds in the presence of weaker C(sp 3 )ÀHb onds is accomplished under these reaction conditions [e.g.b enzylic (6-8), a-oxy (5, 10), a-CF 3 (13), and a-carbonyl (11,12,15,16): 65-75 %y ields].W eo bserved [c] Yield of isolated product after a9hreaction time. [30] Angewandte Chemie Communications exclusive C d ÀHa mination in all cases,i nl ieu of competitive decomposition, or regioisomeric products.…”

Functionalization of cis‐1,4‐polyisoprene using hypervalent iodine compounds with tetrazole ligands

“…Suarez and coworkers demonstrated the use of C 6 H 5 I(O 2 CCH 3 ) 2 ‐I 2 in the acetoxylation of various substrates, and the reaction was further implemented to the iodo‐acetoxylation of olefins . In our previous work, which described the synthesis of HV iodine compounds with tetrazole ligands, we reported the successful iodo‐tetrazolylation, in the presence of elemental iodine, of alkenes such as cyclohexene and styrene.…”