1.4- Dioxaspiro decane-2-methylamine

Dioxaspiro[4.5l decane-2-methylamine 2-Methyl-2-thiopseudourea sulfate... 

A mixture of 10.5 g of l,4-dioxaspiro[4.5]decane-2-methylamine and 8.6 g of 2-methyl-2-thiopseudourea sulfate in 40 ml of water was heated on the steam bath for 4 hours during which 2.0 g of methylmercaptan was collected in a dry ice bath connected to the reaction flask through a water cooled reflux condenser. The reaction mixture was then evaporated at 15 mm pressure to a solid residue which was then dissolved in 80 ml of 50/50 methanol-ethanol. The solution was filtered and evaporated to approximately 50 ml volume and allowed to cool and crystallize, giving a crop melting at 213.5°C to 215°C of l,4-dioxaspiro[4.5]decan-2-ylmethyl)-guanidine sulfate. 

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