Manganese malonate complexes

In other work, solution complex formation of the pendant-arm ligands 1,4,10,13-tetraoxoa-7,16-diazacyclooctadecane-7-malonate and 1,4,10,13-tetraoxoa-7,16-diazacyclooctadecane-7,16-bis(malonate) has been investigated with a range of both transition and nontransition metal ions the 1 1 manganese(II) complexes of these species have been reported to show stabilities (log Ai values) of 7.41 and 5.60, respectively, in water (7=0.15, 25°C). 

Reaction 5. Another aspect of the reaction chemistry of Mn(III) is demonstrated by the classic kinetic studies of the decomposition chemistry of manganese (III) oxalate complexes (35, 36). These studies derive from an earlier discussion of the synthesis of manganese (III)-oxalate compounds (37). A similar set of kinetic and synthetic investigations, have been summarized for the manganese (III )-malonate complexes (38, 39). Both sets of studies confirm that Mn(III) has a particularly strong... 

A novel manganese(iii) complex of the type PPh4[Mn(malonic add)2(H20)2] has been described that incorporates a tetraphenylphosphonium cation and a trans-diaquabis(malonato)manganate(iii) unit. A diphosphinodiphosphonium dication was developed in a two step synthesis. In the st step, dichlorophenylphosphine, triphenylphosphine and trimethylsilyloxy-triflate (TMSOTf) were allowed to react together to give PPhCl-P Phs OTf. Two units of this intermediate then interacted with another molecule of PhsP and TMSOTf to provide the desired dication (Scheme 64). ... 

Several octahedral dihydrazine metal (II) salts of this class were prepared and thermally decomposed. The succinates and malonates of nickel and cadmium decomposed explosively [1]. A later paper on mixed metal bis-hydrazine malonates of cobalt with magnesium, manganese, nickel, zinc or cadmium recommends that decomposition, in a pre-heated crucible at 500°C, be of small quantities only. The same workers have reported exothermic decomposition of similar hydrazine complexed salts of other small organic acids. 

Preparative procedures for Mn(HS04)278 and manganese(n) malonate dihydrate79 have been published. Ethylene glycol (EG) forms the complexes Mn(EG) An... 

The tetranuclear magnesium chelate complexes [(NH4)4n Mg4(L10 n)6 ] (29a,b) were first synthesized by reaction of dialkyl malonate 28, methylmagnesium iodide, and oxalyl chloride, followed by workup in aqueous ammonium chloride solution [102-105]. Now methyllithium/magnesium chloride instead of methylmagnesium iodide (direct method) is used, which by mere replacement of magnesium chloride by the chlorides of manganese, cobalt, and nickel also allows the synthesis of the corresponding tetranuclear complexes 29 (with Mn = Mn2+, Co2+, Ni2+) [103, 105]. 

The first example of chiral tetranuclear supramolecular assembly 5.27 was reported by Saalfrank and coworkers in 1988. Thus the complex [(NH3)4n(Mg (22)5] (5.27) was obtained by serendipity upon treatment of the doubly bidentate ligand 22, which is formed in situ from malonic ester and oxalyl chloride, with MeMgl in aqueous ammonium chloride solution (Scheme 5.13). Later an improved one-pot reaction was used to prepare such tetrahedral complexes of magnesium, manganese, cobalt and nickel by treating the bis(chelate) ligand 22, obtained in situ, with MeLi/MCl2 followed... 

---