A two-step process was developed for the preparation of triacetylglycerol (TAG), a biofuel additive employing a solid acid catalyst derived from glycerol. The first step involves esterification of glycerol with acetic acid (1:4 mol) at 115 °C for 1 h in the presence of catalyst (5 wt %) to obtain 100% conversion of glycerol with 22, 67, and 11% MAG, DAG, and TAG, respectively. In the second step, the esterified product mixture after removal of excess acetic acid and moisture was acetylated with acetic anhydride (1 mol with respect to glycerol) at 115 °C for 30 min to obtain 100% TAG. The recovered catalyst was reused for five cycles without any significant loss of its initial activity. The protocol is cost-effective due to the use of highly stable and recyclable SO3H-carbon catalyst for the production of TAG with minimum moles of acetic acid and acetic anhydride in shorter reaction time.

KEYWORDSGlycerol-based SO3H-functionalized carbon catalyst was demonstrated as an efficient and recyclable green catalyst for the chemoselective synthesis of pentaerythritol diacetals with aromatic aldehydes in the presence of ketones in excellent yields in toluene at 80 C. In addition, the catalyst also has the capability for the deprotection of pentaerythritol diacetals in methanol at reflux temperature. The recovered catalyst without any pre-treatment was reused for 5 cycles without any deactivation and leaching into the reaction medium under optimum conditions. Reusability Chemoselectivity Aromatic aldehydes Pentaerythritol diacetals Glycerol-based SO3H-carbon catalyst Protection and deprotection of diacetals

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Dendrimers and hyperbranched polymers may have structural resemblance, but they are different from each other in their topological structures. The potentials of dendrimers and hyperbranched polymers are reported to have various applications in different fields such as material science, nanotechnology, supramolecular chemistry, biomaterials, coatings, adhesives, etc. In this chapter we discuss antimicrobial applications of dendrimers and hyperbranched polymers.

A Novel One-Pot Synthesis of Spiro[indoline-3,4'-pyrazolo[3,4-e][1,4]thiazepine]diones Using Recyclable Bioglycerol-Based Sulfonic Acid FunctionalizedCarbon Catalyst. -The simple protocol allows the rapid access to biologically important scaffolds such as (IV) and (VII). -(KARNAKAR, K.; MURTHY, S. N.; RAMESH, K.; REDDY, K. H. V.; NAGESWAR*, Y. V. D.; CHANDRAKALA, U.; DEVI, B. L. A. P.; PRASAD, R. B. N.; Tetrahedron Lett. 53 (2012) 27, 3497-3501, http://dx.