Sandip A. Sadaphal

Ionic liquid promoted synthesis of bis(indolyl) methanes

Abstract1-benzyl-3-methyl imidazolium hydrogen sulphate [bnmim][HSO4] was found to be an effective catalyst for the condensation reaction of indoles and derivatives with benzaldehydes in microwave irradiation with lower reaction time and higher yields to give bis(indolyl) methanes.

An Efficient Synthesis and Antibacterial Screening of Novel Oxazepine α-Aminophosphonates by Ultrasound Approach

An efficient synthesis of novel α-aminophosphonates by the reaction of quino[2,3-b][1,5]benzoxazepines with triethyl phosphite in the presence of the easily available, inexpensive, and nontoxic catalyst p-toluene sulphonic acid (p-TSA). This method affords the α-aminophosphonates under the influence of ultrasound irradiation in solvent-free conditions, in short reaction times (4–6 min), high yields (80–90%), with improved purity. The synthesized α-aminophosphonates show antibacterial activity against Gram-positive and Gram-negative bacteria. Supplemental materials are available for this article. Go to the publishers online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

Cellulose sulfuric acid: reusable catalyst for solvent-free synthesis of bis(indolyl)methanes at room temperature

Abstract Bis(indolyl)methanes were synthesized from indole and aldehydes under solvent-free conditions using cellulose sulfuric acid (CSA) as a catalyst at room temperature. CSA is easily prepared and it was also found that this catalyst could be recovered quantitatively and reused without much loss of catalytic activity.

Alum catalyzed simple and efficient synthesis of 5-arylidene-2,4-thiazolidinedione in aqueous media

Abstract Alum (KAl(SO4)2·12H2O) is an inexpensive, efficient, and non-toxic catalyst used for the synthesis of 5-arylidine-2,4-thiazolidinediones by the Knoevenagel condensation of aromatic aldehydes with 2,4-thiazolidinedione in aqueous media at 90°C. This method affords the 5-arylidine-2,4-thiazolidinediones in short reaction times, high yields, and green aspects by avoiding toxic catalysts and hazardous solvents.

PEG-400 remarkably efficient and recyclable media for one-pot synthesis of various 2-amino-4H-chromenes

Abstract Polyethylene glycol-400 has been found to be a recyclable and rapid reaction medium for the synthesis of 2-amino-4H-chromenes by the condensation of aromatic aldehyde, malononitrile, and α-naphthol. This method gives remarkable advantages such as simple work up, high yields, and a greener method by avoiding toxic catalyst and hazardous solvents.

Water mediated synthesis of various [1,3]oxazine compounds using alum as a catalyst

Abstract A simple, efficient, and practical procedure for the synthesis of various substituted 2,3-dihydro-2-phenyl-1H-naphtho[1,2-e][1,3]oxazines and 3,4-dihydro-3-phenyl-2H-naphtho[2,1-e][1,3]oxazines using KAl(SO4)2 12H2O (alum) as a non-toxic, reusable, inexpensive, and easily available catalyst is described using water as a solvent. These improved reaction conditions allow the preparation of a wide variety of substituted [1,3]oxazines in high yields and purity under mild reaction conditions.

An efficient synthesis of α-hydroxyphosphonates and α-aminophosphonates in the presence of chlorotrimethylsilane

Abstract Solvent free, and quantitative yielding synthesis of α-hydroxyphosphonates (2a–h) from 2-chloroquinolin-3-carbaldehyde (1a–h) and α-aminophosphonates (4a–p) from imines (3a–p), obtained from 2-chloroquinoline-3-carbaldehyde by using triethylphosphite in the presence of chlorotrimethylsilane at room temperature in short time.