Enantioselective Ir-catalyzed allylic aminations with hydroxamic acid derivatives are described. Catalysts were prepared in situ from [Ir(cod)Cl](2) or [Ir(dbcot)Cl](2), a phosphoramidite and base. In addition, pure (π-allyl)Ir complexes containing cod or dbcot as auxiliary ligands were used. Very high degrees of regio- and enantioselectivity were achieved. The reaction products were transformed into piperidine derivatives suited as precursors for aza-sugars.
Higher homologues of dibenzo[
c
,
e
][1,2]dithiin were synthesized from oligophenyls bearing multiple methylthio groups. Single‐crystal X‐ray analyses revealed their nonplanar structures and helical enantiomers of higher
meta
‐congener
6
. Such dibenzo[1,2]dithiin homologues are demonstrated to be applicable to lithium‐ion batteries as cathode, displaying a high capacity of 118 mAh g
−1
at a current density of 50 mA g
−1
.
The silylmethylene-linked triamidophosphine P(CH2SiMe2NHPh)3 was isolated in form of its tri-lithium salt Li3[P(CH2SiMe2NPh)3]·2.5Et2O (1·2.5Et2O) and employed for the synthesis of titanium and zirconium complexes. Starting from 1·2.5Et2O, the chlorido complexes [κ(4)-N,N,N,P-PN3]MCl (4-M, M = Ti, Zr) were prepared and examined with respect to alkylation. Upon reaction of 4-Ti with (trimethylsilyl)methyl lithium, intra-ligand cyclometalation at one of the ortho-N-phenyl positions was observed and the resulting thermally stable titanazetidine [κ(5)-N,N,N,P,C-N2P(NC)]Ti (5-Ti) isolated. Similarly, the related zirconazetidine [κ(5)-N,N,N,P,C-N2P(NC)]Zr(THF) (5-Zr) was isolated upon reaction of 4-Zr with Bn2Mg(THF)2. Using LiCH2PMe2 as alkyl transfer reagent, both complexes 4-M were converted to the corresponding phosphametallacyclopropanes [κ(4)-N,N,N,P-PN3]M(κ(2)-C,P-CH2PMe2) (7-M, M = Ti, Zr). Upon gentle heating, complexes 7-M were cleanly converted to the cyclometalated species 5-M and trimethylphosphine. These results are discussed in the context of related amidophosphine and triamidoamine complexes.
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