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Metal-Mediated Addition of N-Nucleophiles to Isocyanides: Mechanistic Aspects.

ABSTRACT: Despite the long history of the investigation of nucleophilic addition to metal-bound isocyanides, some important aspects of the reaction mechanism remain unclear even for the simplest systems. In this work, the addition of the sp³-N, sp²-N, and mixed sp²/sp³-N nucleophiles (i.e., HNMe?, HN=CPh?, and H?N-N=CPh?, respectively) to isocyanides C?NR coordinated to the platinum(II) centers in the complexes cis-[Pt(C?NCy)(2-pyz)(dppe)]? (2-pyz = 2-pyrazyl, dmpe = Me?PCH?CH?PMe?) and cis-[PtCl?(C?NXyl)(C?NMe)] was studied in detail by theoretical (DFT) methods. The mechanism of these reactions is stepwise associative rather than concerted and it includes the addition of a nucleophile to the isocyanide C atom, deprotonation of the nucleophilic moiety in the resulting intermediate, and protonation of the isocyanide N atom to give the final product. The calculated activation energy (?G^?) of all reactions is in the range of 19.8-22.4 kcal/mol.

SUBMITTER: Kuznetsov ML

PROVIDER: S-EPMC6152363 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Metal-Mediated Addition of N-Nucleophiles to Isocyanides: Mechanistic Aspects.

Kuznetsov Maxim L ML Kukushkin Vadim Yu VY

Molecules (Basel, Switzerland) 20170708 7

Despite the long history of the investigation of nucleophilic addition to metal-bound isocyanides, some important aspects of the reaction mechanism remain unclear even for the simplest systems. In this work, the addition of the sp³-N, sp²-N, and mixed sp²/sp³-N nucleophiles (i.e., HNMe₂, HN=CPh₂, and H₂N-N=CPh₂, respectively) to isocyanides C≡NR coordinated to the platinum(II) centers in the complexes <i>cis</i>-[Pt(C≡NCy)(2-pyz)(dppe)]⁺ (2-pyz = 2-pyrazyl, dmpe = Me₂PCH₂CH₂PMe₂) and <i>cis</i>- ...[more]

PMID: 28698454

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