Si-CDO was synthesized hydrothermally via the topotactic conversion of a pre-CDO layered silicate that to RUB-37 (i.e., Si-CDO). First, commercial DEDMA-OH solution was dehydrated until a concentration of 23.6% was reached. Then, 5.16 g of fumed silica was combined with 19.02 g of the preconcentrated DEDMA-OH solution. After 15 minutes stirring, a thick, white gel is yielded with a molar composition of 1 SiO 2 : 0.44 DEDMA-OH : 9.45 H 2 O. This gel was transferred into a teflon-lined autoclave, which was heated to 423 K in a convection oven for 13 days. The resulting solids were recovered by filtration, washed with H 2 O, and dried at 353 K for 12 h to yield 3.70 g RUB-36 (i.e., a pre-CDO silicate). RUB-36 was then heated in flowing air to 923 K at 2 K min -1 and held for 4 h to produce Si-CDO, that is bleached white in appearance.