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A series of sulphate modified Al-MCM-41 acid catalysts are synthesized following impregnation and co-condensation methods The physico-chemical characterizations of all the samples are done by XRD, FT-IR, TGA/DTA, TPD, N 2 adsorption and desorption study, SEM, HRTEM and EDAX etc. The structural advantages of Al-MCM-41 such as large specific surface area, wide pore size and pore volume and Bronsted and Lewis acid sites favor the coupling reaction. The catalysts endorsed the direct addition of alcohols to alkynes as well as their coupling with styrenes. The various combinations of alcohols with alkynes and styrenes are compatible with diverse functional groups to synthesize a substituted aryl ketones, as well as olefins with good to excellent yields. Additionally, the approach is advantageous in terms using alcohols, discounting the pre-functionalization and generation of waste by-products. Used precursors, alkynes and styrenes, are valuable since they are stable and found in many biologically active compounds. This current research work provides supplements to C C bond formation methodologies as a single step with atom economy and recyclable approach under mild and environmentally benign conditions.

The construction of C3-symmetric triarylbenzenes via cyclotrimerization of alkynes using Amberlyst-15/1-butyl-3-methylimidazolium hexafluorophosphate [Bmim][PF6] has been developed. The catalytic system works well for various substrates under milder reaction conditions. The developed methodology is operationally simple, and metal-free, solvent-free, and additive-free reactions with excellent yields make it good for synthetic utility. The recyclability of the Amberlyst-15/[Bmim][PF6] as well as 100% atom efficiency makes the developed protocol more green.

The direct α-alkylation of acetophenones with benzhydrols as well as 1-phenylethanols using Amberlyst-15/[Bmim][PF6] ionic liquid as an affordable catalytic system has been developed. This protocol provides a simple, mild, metal-free method for the synthesis of alkylated carbonyl compounds in good to excellent yields. Further, the developed methodology is moisture-stable and operationally simple and can be recycled up to four cycles without much significant loss in its catalytic activity.

A highly efficient protocol for the synthesis of substituted aryl ketones by using Amberlyst-15 immobilized in [Bmim][PF 6 ] ionic liquid has been firstly developed. The present protocol works under metal-free, solvent-free, mild reaction conditions with 100% atom efficiency. The various aryl ketones were obtained in good to excellent yields. The developed catalytic system was recycled efficiently up to five cycles without significant loss in catalytic activity.

This work reports a novel and efficient protocol for the synthesis of 2-phenylnaphthalenes from styrene oxides using a recyclable ionic liquid. The ionic liquid N-methyl-2-pyrrolidone hydrogensulfate [HNMP]+HSO4− played the dual role of a catalyst and a solvent. It efficiently constructs 2-phenylnaphthalene and its derivatives in excellent yields with much simplicity in the operation. The present protocol has higher atom efficiency and wider substrate applicability. The [HNMP]+HSO4− has been effectively recycled for up to five consecutive cycles without appreciable loss in its activity.

A novel protocol for the synthesis of substituted alkenes from alcohols and styrenes using ionic liquid has been developed. The ionic liquid N-methyl-2-pyrrolidone hydrogen sulfate [NMP]+HSO4− acts as a catalyst as well as solvent. The developed protocol has higher atom efficiency and wider substrate applicability. The catalyst was effectively recycled for up to five consecutive cycles.

Mucoadhesive buccal films were developed using tamarind seed xyloglucan (TSX) as novel mucoadhesive polysaccharide polymer for systemic delivery of rizatriptan benzoate through buccal route. Formulations were prepared based on 3(2) factorial design with concentrations of TSX and carbopol 934P (CP) as independent variables. Three dependent variables considered were tensile strength, bioadhesion force and drug release. DSC analysis revealed no interaction between drug and polymers. Ex vivo diffusion studies were carried out using Franz diffusion cell, while bioadhesive properties were evaluated using texture analyzer with porcine buccal mucosa as model tissue. Results revealed that bilayer film containing 4% (w/v) TSX and 0.5% (w/v) CP in the drug layer and 1% (w/v) ethyl cellulose in backing layer demonstrated diffusion of 93.45% through the porcine buccal mucosa. Thus, this study suggests that tamarind seed polysaccharide can act as a potential mucoadhesive polymer for buccal delivery of a highly soluble drug like rizatriptan benzoate.

the ionic liquid, which acts both as a catalyst and solvent, is recyclable and reusable up to 5 times with only a slight decline in yield