II Complex of the Ring Contracted Macrocycle

Analogous metal-promoted ring contractions of L to may be carried out using salts of Mn(II), Fe(ll), and Zn(II) in place of Co(lI).  

Shannon, Acta Cryst., A32, 751 (1976). The values quoted in the text refer to the octacooidinate ions. 

To a suspension of 1.17 g (0.001 mole) of [Bal KClO in 800 mL of methanol, in a 2-L round-bottomed flask fitted with a reflux condenser, is added 2.2 g (0.006 mole) of solid cobalt(U) perchlorate hexahydrate. The mixture is gently refluxed until the Ba(II) complex has completely dissolved, which may take two to three days. After the solution becomes clear, the reflux should be continued for an additional two hours. The orange solution is then concentrated to a volume of about SO mL by rotary evaporation and then set aside in a beaker to crystallize. The orange crystals which separate are filtered, washed with cold methanol, and dried in air. Yield 60%. Anal. Calcd. for C HmOuNgC Co C, 44.60 H, 3.74 N, 11.15. Found C, 44.26 H, 3.61 N, 11.00. 

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