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Coordination Chemistry and Methylation of Mixed-Substituted Tetraphosphetanes (RP-PtBu)2 (R=Ph, Py).

ABSTRACT: Synthesis of mixed-substituted tetraphosphetanes (RP-PtBu)2 (R=Ph (4), Py (5); Py=2-pyridyl) is achieved from the condensation of dipyrazolylphosphanes RPpyr2 (R=Py (1), Ph (3); pyr=3,5-dimethylpyrazolyl) as P1 -building block (R-P) and tBuPH2 in an equimolar ratio. Compound?5 is of special interest since the presence of two pyridyl-substituents as well as the P4 -core allows for a rich coordination chemistry with coinage metal salts [Cu(MeCN)4 ][OTf], Ag[OTf] and in situ formed [Au(tht)][OTf] (tht=tetrahydrothiophene). Both tetraphosphetanes undergo alkylation reaction with MeOTf to give a series of tetraphosphetanium and tetraphosphetanediium triflate salts with additional methylation of the pyridyl-moiety in case of 5 resulting in interesting novel cyclic trications. Harsh reaction condition and an excess of MeOTf converts 5 into the cyclic trication [-P(Me Py)PMe2 P(Me Py)PtBu-]3+ (133+ ; Me Py=1-methylpyridiniumyl) through the elimination of isobutene. This salt undergoes a complicated rearrangement reaction involving a P-P/P-P bond metathesis to form trication [-P(MePy)3 PtBu-]3+ (173+ ) when reacted with Me2 PPMe2 .

SUBMITTER: Schoemaker R

PROVIDER: S-EPMC7540047 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Coordination Chemistry and Methylation of Mixed-Substituted Tetraphosphetanes (RP-PtBu)2 (R=Ph, Py).

Schoemaker Robin R Kossatz Philipp P Schwedtmann Kai K Hennersdorf Felix F Weigand Jan J JJ

Chemistry (Weinheim an der Bergstrasse, Germany) 20200817 51

Synthesis of mixed-substituted tetraphosphetanes (RP-PtBu)2 (R=Ph (4), Py (5); Py=2-pyridyl) is achieved from the condensation of dipyrazolylphosphanes RPpyr2 (R=Py (1), Ph (3); pyr=3,5-dimethylpyrazolyl) as P1 -building block (R-P) and tBuPH2 in an equimolar ratio. Compound 5 is of special interest since the presence of two pyridyl-substituents as well as the P4 -core allows for a rich coordination chemistry with coinage metal salts [Cu(MeC ...[more]

PMID: 32557881

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Dataset Information

Coordination Chemistry and Methylation of Mixed-Substituted Tetraphosphetanes (RP-PtBu)2 (R=Ph, Py).

Publications

Coordination Chemistry and Methylation of Mixed-Substituted Tetraphosphetanes (RP-PtBu)<sub>2</sub> (R=Ph, Py).

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