The mechanism of the intermolecular hydroamination of 3‐methylbuta‐1,2‐diene (
This content will become publicly available on May 17, 2025
This computational study explores the copper (I) chloride catalyzed synthesis of (E)‐1‐(2,2‐dichloro‐1‐phenylvinyl)‐2‐phenyldiazene (
- Award ID(s):
- 2152633
- PAR ID:
- 10507940
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Journal of Computational Chemistry
- ISSN:
- 0192-8651
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract 1 ) withN ‐methylaniline (2 ) catalyzed by (IPr)AuOTf has been studied by employing a combination of kinetic analysis, deuterium labelling studies, and in situ spectral analysis of catalytically active mixtures. The results of these and additional experiments are consistent with a mechanism for hydroamination involving reversible, endergonic displacement ofN ‐methylaniline from [(IPr)Au(NHMePh)]+(4 ) by allene to form the cationic gold π‐C1,C2 ‐allene complex [(IPr)Au(η2‐H2C=C=CMe2)]+(I ), which is in rapid, endergonic equilibrium with the regioisomeric π‐C2,C3 ‐allene complex [(IPr)Au(η2‐Me2C=C=CH2)]+(I′ ). Rapid and reversible outer‐sphere addition of2 to the terminal allene carbon atom ofI′ to form gold vinyl complex (IPr)Au[C(=CH2)CMe2NMePh] (II ) is superimposed on the slower addition of2 to the terminal allene carbon atom ofI to form gold vinyl complex (IPr)Au[C(=CMe2)CH2NMePh] (III ). Selective protodeauration ofIII releasesN ‐methyl‐N ‐(3‐methylbut‐2‐en‐1‐yl)aniline (3 a ) with regeneration of4 . At high conversion, gold vinyl complexII is competitively trapped by an (IPr)Au+fragment to form the cationic bis(gold) vinyl complex {[(IPr)Au]2[C(=CH2)CMe2NMePh]}+(6 ). -
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Abstract Low‐temperature reaction of the tris(pyrazolyl)borate copper(II) hydroxide [iPr2TpCu]2(μ‐OH)2with triphenylsilane under a dinitrogen atmosphere gives the bridging dinitrogen complex [iPr2TpCu]2(μ‐1,2‐N2) (
3 ). X‐ray crystallography reveals an only slightly activated N2ligand (N‐N: 1.111(6) Å) that bridges between two monovalentiPr2TpCu fragments. While DFT studies of mono‐ and dinuclear copper dinitrogen complexes suggest weak π‐backbonding between the d10CuIcenters and the N2ligand, they reveal a degree of cooperativity in the dinuclear Cu‐N2‐Cu interaction. Addition of MeCN, CNAr2,6‐Me, or O2to3 releases N2with formation ofiPr2TpCu(L) (L=NCMe, CNAr2,6‐Me2) or [iPr2TpCu]2(μ‐η2:η2‐O2) (1 ). Addition of triphenylsilane to [iPr2TpCu]2(μ‐OH)2in pentane allows isolation of a key intermediate [iPr2TpCu]2(μ‐H) (5 ). Although5 thermally decays under N2to give3 , it reduces unsaturated substrates, such as CO and HC≡CPh to HC(O)H and H2C=CHPh, respectively. -
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Abstract Decarbonylation along with P‐atom transfer from the phosphaethynolate anion, PCO−, to the NbIVcomplex [(PNP)NbCl2(N
t BuAr)] (1 ) (PNP=N[2‐Pi Pr2‐4‐methylphenyl]2−; Ar=3,5‐Me2C6H3) results in its coupling with one of the phosphine arms of the pincer ligand to produce a phosphanylidene phosphorane complex [(PNPP)NbCl(Nt BuAr)] (2 ). Reduction of2 with CoCp*2cleaves the P−P bond to form the first neutral and terminal phosphido complex of a group 5 transition metal, namely, [(PNP)Nb≡P(Nt BuAr)] (3 ). Theoretical studies have been used to understand both the coupling of the P‐atom and the reductive cleavage of the P−P bond. Reaction of3 with a two‐electron oxidant such as ethylene sulfide results in a diamagnetic sulfido complex having a P−P coupled ligand, namely [(PNPP)Nb=S(Nt BuAr)] (4 ). -
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t BuAr)] (1 ) (PNP=N[2‐Pi Pr2‐4‐methylphenyl]2−; Ar=3,5‐Me2C6H3) results in its coupling with one of the phosphine arms of the pincer ligand to produce a phosphanylidene phosphorane complex [(PNPP)NbCl(Nt BuAr)] (2 ). Reduction of2 with CoCp*2cleaves the P−P bond to form the first neutral and terminal phosphido complex of a group 5 transition metal, namely, [(PNP)Nb≡P(Nt BuAr)] (3 ). Theoretical studies have been used to understand both the coupling of the P‐atom and the reductive cleavage of the P−P bond. Reaction of3 with a two‐electron oxidant such as ethylene sulfide results in a diamagnetic sulfido complex having a P−P coupled ligand, namely [(PNPP)Nb=S(Nt BuAr)] (4 ). -
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