Carbodiimide insertion reactions of homoleptic heavier alkaline earth amides and phosphides

Anthony G M Barrett, Mark R Crimmin, Michael Hill, Peter B Hitchcock, Sarah L Lomas, Mary F Mahon, Panayiotis A Procopiou

Research output: Contribution to journalArticle

32 Citations (Scopus)

Abstract

A series of homoleptic guanidinate-type complexes of the heavier alkaline earth (Ae) metals calcium and strontium have been prepared. The six-coordinate compounds [Ae{iPrNC(NPh2)CNiPr} 2(THF)2] (Ae = Ca and Sr) were synthesised through reactions of the appropriate THF-solvated hexamethyldisilazide [Ae{N(SiMe 3)2}2(THF)2] with two molar equivalents of diphenylamine and 1,3-di-iso-propylcarbodiimide. Both compounds were shown to crystallise with a cisoid arrangement of the two THF molecules at the metal centres. In contrast, the (Me3Si)2N-substituted calcium guanidinate, [Ca{CyNC{N(SiMe3)2}CNCy} 2(THF)2], contains two coordinated THF molecules with a trans disposition. Further reactions of the free amidine [{(2-FC 6H4)N}C(NHiPr)2] with either [Ca{N(SiMe3)2}2(THF)2] or its dimeric unsolvated analogue provided monomeric or dimeric derivatives respectively in which the ligands had tautomerised to an anisobidentate form. A further reaction of the phosphaguanidine [CyNC(PPh2)N(H)Cy] with [Sr{N(SiMe3)2}2(THF)2] provided the first example of a phosphaguanidinate complex of this heavier alkaline earth metal. This compound has also been characterised in the solid state and shown to exist with a transoid configuration of the coordinated THF molecules.
Original languageEnglish
Pages (from-to)7393-7400
Number of pages8
JournalDalton Transactions
Volume39
Issue number31
DOIs
Publication statusPublished - 21 Aug 2010

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Carbodiimides
Alkaline Earth Metals
Amides
Earth (planet)
Heavy metals
Molecules
Amidines
Diphenylamine
Calcium
Strontium
Metals
Ligands
Derivatives

Cite this

Barrett, A. G. M., Crimmin, M. R., Hill, M., Hitchcock, P. B., Lomas, S. L., Mahon, M. F., & Procopiou, P. A. (2010). Carbodiimide insertion reactions of homoleptic heavier alkaline earth amides and phosphides. Dalton Transactions, 39(31), 7393-7400. https://doi.org/10.1039/c0dt00089b

Carbodiimide insertion reactions of homoleptic heavier alkaline earth amides and phosphides. / Barrett, Anthony G M; Crimmin, Mark R; Hill, Michael; Hitchcock, Peter B; Lomas, Sarah L; Mahon, Mary F; Procopiou, Panayiotis A.

In: Dalton Transactions, Vol. 39, No. 31, 21.08.2010, p. 7393-7400.

Research output: Contribution to journalArticle

Barrett, AGM, Crimmin, MR, Hill, M, Hitchcock, PB, Lomas, SL, Mahon, MF & Procopiou, PA 2010, 'Carbodiimide insertion reactions of homoleptic heavier alkaline earth amides and phosphides', Dalton Transactions, vol. 39, no. 31, pp. 7393-7400. https://doi.org/10.1039/c0dt00089b
Barrett, Anthony G M ; Crimmin, Mark R ; Hill, Michael ; Hitchcock, Peter B ; Lomas, Sarah L ; Mahon, Mary F ; Procopiou, Panayiotis A. / Carbodiimide insertion reactions of homoleptic heavier alkaline earth amides and phosphides. In: Dalton Transactions. 2010 ; Vol. 39, No. 31. pp. 7393-7400.
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