An object of the present invention is to provide a positive electrode active material for a nonaqueous electrolyte secondary battery etc. The invention also relates to the use of silicon produced in this way and to highly pure, granular silicon particles which are characterised by a coreless structure. Advantageously, the natural static pressure difference between these points results in a self-aspirating assembly. By using a VM placeholder, a VM may appear to be active and selectable by the user. More specifically disclosed is a method for producing 4,6-dialkoxy-2-cyanomethylpyrimidine represented by general formula, comprising reacting a t-butyl cyanoacetate derivative represented by general formula in the presence of an acid, and also disclosed is a t-butyl cyanoacetate derivative represented by general formula. The second receiving channel optionally includes an RSSI.