One-Pot Reaction Cascades Catalyzed by Base and Acid Confined Inside Pores of Mesoporous Silica Nanospheres

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1 One-Pot Reaction Cascades Catalyzed by Base and Acid Confined Inside Pores of Mesoporous Silica Nanospheres Yulin Huang, Brian Trewyn, Hung-ting Chen, Shu Xu, Victor S.-Y. Lin* Department of Chemistry and Ames Laboratory, Iowa State University, Ames, IA5 Synthesis of mesoporous silica nanosphere (MSN) containing organic acid confined inside pores (SAMSN) and MSN conaiting organic base confined inside pores (APMSN) SAMSN and APMSN were synthesized via the co-condensation reaction from our group. A typical procedure is as following: A mixture of cetyltrimethylammonium bromide (CTAB, 5.9 mmol),. mol / L of aqueous NaOH (7 ml, mmol) and water (8 ml, 6.67 mol) was heated at 8 oc for min. Into this clear solution, tetraethylorthosilicate (TEOS, ml, 5. mmol) and. mmol of -(chlorosulfonylphenyl)ethyltrimethoxysilane for SAMSN (or -aminopropyltrimethoxysilane for APMSN) were added rapidly and sequentially via injection with vigorous stirring. Within few minutes, the white solid precipitate was observed. After hours, the as-synthesized material was separated by hot filtration, washed with copious amount of methanol, dried under vacuum overnight. The surfactant (CTAB) was removed b y acid extraction at 6 oc with vigorous stirring by placing. gram of as-made solid in ml methanol including. ml concentrated hydrochloride acid for 6 hours. The resulted surfactant-removed solid SAMSN (or APMSN) was collected by hot filtration, washed with copious amount of water and methanol, dried at 9 oc under vacuum overnight.. Characterization of MSB-acid and APMSN (a) (b) Figure S. Scanning electron microscopy (SEM) of SAMSN (a) and APMSN (b).

2 MSN-acid MSN-base Intensity (a.u.) θ (deg) Figure S. Powder XRD data of SAMSN and APMSN. Volume adsorbed (cm/g STP) 5 Adsorption 5 Desorption Relative pressure (P/Po)

3 Pore volume - dv/dlogd (cm/g) Pore diameter - D (Å) ( a ) SAMSN Volume adsorbed (cm/g STP) 6 5 Adsorption Desorption Relative pressure (P/Po) Pore volume - dv/dlogd (cm/g) Pore width - D (Å) ( b ) APMSN Figure S. BET isotherms and BJH pore diameter distribution curves of SAMSN and APMSN.

4 Figure S. 9 Si solid state NMR spectrum of SAMSN (T : -59 ppm; T : -68 ppm; Q : -9 ppm; Q : - ppm; Q : - ppm). Figure S5. 9 Si solid state NMR spectrum of APMSN (T : -59 ppm; T : -68 ppm; Q : -9 ppm; Q : - ppm; Q : - ppm). Table S. Structrual data of SAMSN and APMSN. a Samples d (Å) S BET (m g - ) V p (cm g - ) D BJH (Å) SAMSN APMSN [a] The BET surface area (S BET ), the mesopore volume (V p ), and the mean mesopore diameter (D BJH ) were obtained from the nitrogen absorption / desorption data in Figure S. The d data represent the d-spacing corresponding to the () peaks in XRD (Figure S).

5 . One-pot reaction cascades -nitrobenzaldehyde dimethyl acetal (.75 mmol) and water (.75 mmol) were mixed with SAMSN (or free acid, and the acid quantity is decided by the reaction conditions) and APMSN (or free base, and the base quantity is decided by the reaction conditions) at room temperature under N and sealed in a glass vessel. The as-made slurry was heated to 8 o C with vigorous stirring. After hours, the reaction was stopped by cooling to room temperature. The product was analyzed by GC-MS with capillary column (HP-5, m x.9 mm x.5 μm). () Huh, S.; Wiench, J.W.; Yoo, J.C.; Pruski, M.; Lin, V.S.Y. Chem. Mater., 5, () Huh, S.; Wiench, J.W.; Trewyn, B.G.; Song, S.; Pruski, M.; Lin, V.S.Y. Chem. Commun., 6. () Radu, D.R.; Lai, C.Y.; Huang, J.; Xu, S.; Lin, V.S.Y. Chem. Commun. 5,