alkanedisulfamic acid functionalized silica-coated magnetic nanoparticles (adsa-mnps) were used as effective, low-cost and reusable solid heterogeneous nanomagnetic catalysts for conversion of aldehydes and ketones to corresponding gem-dihydroperoxides and 1,2,4,5-tetraoxanes using aqueous hydrogen peroxide (30% w/w in h2o) at room temperature. these compounds are important key intermediates in...