Dmso Synthesis

Using the ethanol as the solvent produces a more environmentally favorable conditions, and the bleach combined with sodium iodide produces an efficient and selective (mono-) product. Once the final product had been recrystallized with isopropanol, the crystal were collected via vacuum filtration. These crystals took some time to dry out, but they eventually were dry enough to scrape out for further evaluation. After an IR was run, it was quite obvious the product was surely Iodovanillin. Further analysis of the melting point was taken to ensure the final product was the desired Iodovanillin.

Isoamyl acetate was synthesized by refluxing 1 eq of isopentanol with 4 eq of acetic acid, and 0.5 eq of concentrated sulfuric acid as a catalyst and a dehydrating agent to ensure reaction equilibrium lies far towards the products. The reaction mixture was then added to water and liquid-liquid extraction was conducted. A second extraction was then conducted after adding NaHCO3 solution to the organic layer. This removes the residual acids which are soluble in the aqueous layer. Drying of the crude ester with anhydrous MgSO4 removes H2O that disrupts the NMR and infrared spectrum, hindering the characterization of the product formed.

These substances show a RDA cleavage-phenomenon in their mass spectrum, and through this their structure and molecular formula are determined.

The raw atenolol and metoprolol powder were the kind gift from Swiss Pharmaceutical Co., Ltd, Taiwan. Chemically, atenolol (free base) and metoprolol have a molecular weight of 266 and 267 (Lennernasi, et al., 1994; Gros, et al., 2006b), the melting point between 152℃ and 156.5℃ (USP, 2005). It is a relatively polar hydrophilic compound with a water solubility of 13.3 mg/mL at 25℃(Gros, et al., 2006b). The extent of ATN molecule was estimated to be 7x18.2 Å (Lennernasi, et al., 1994, Sybyl®; Fagerholm, et al., 1999). The pka of ATN and MTN were 9.6 and 9.7(24℃) (Lennernasi, et al., 1994). Since the compound was in protonated form at pH < pka, which the solution was basic, the neutral ATN and MTN molecules are the dominant specie (Pasti et al., 2013). The surface areas were 34.1±2 Å2 (Seelig, et al., 1994). The dynamic volume were 343 and 364 Å3 for ATN and MTN, respectively (Palm, et al., 1997). An awesome feature of beta blockers is that they have been reported to behave as weak cationic surfactants at neutral pH (Mosquera et al., 1999).

The ethyl (3-oxo-2,3-dihydro-4H-1,4-benzothiazin-4-yl)acetate 4C (0.05 mol, 14.37g) was warmed in a mixture of ethanol and DMF (1:2) to get a clear solution and was cooled to room temperature. A solution of KOH (0.08 mol, 4.81g) in water (10 ml) was added to this solution and the mixture was stirred for 24h at room temperature to ensure the completion of the reaction. The completion of the reaction was monitored by TLC (CHCl3:MeOH, 9:1). The reaction mixture was evaporated to dryness and the residue dissolved again by adding ice cold water. The insoluble impurities were separated by filtration and the filtrate was acidified with 4N HCl to get a solid product (3-oxo-2,3-dihydro-4H-1,4-benzothiazin-4-yl)acetic acid (4D), collected by filtration.

After the functional groups are determined from the IR spectrum, 1H-NMR should be used so that clues to the connectivity of the molecule can be uncovered. After analyzing the data from

Bis(2-chloroethy1)aminophosphoric dichloride (73.5g, 28.4mmol) is dissolved in THF (150mL).6 A solution of 3-aminopropanol (21.3g, 28.4mmol) is dissolved in a separate bath of THF (150mL), and triethylamine (79.0mL) is added.6 These two solutions are simultaneously added dropwise into stirred dry THF (300mL) over 3 h.6 Once both of the solutions have been added, the reaction is left overnight at room temperature, with continuous stirring.6 The resulting solution is then vacuum filtered as to remove the Triethylammonium hydrochloride, and the filtrate will evaporate under vacuum.6 The remaining residue is then subject the silica gel chromatography (100g), with chloroform-methanol.6 This should result in a colourless oil, which is dried under vacuum over P401o. The dried substance is then recyrstallised from dry ether at -78oC.6 This chemical synthesisV was reported by Verkade in 1978. Verkade and his research team reported a yield of

The IR spectrum of 8a showed stretching bands for the N−H bond at 3357 cm–1 and for C=O bonds of the lactone and ester functionalities at 1733, 1677 and 1614 cm–1. The mass spectrum of 8a displayed the molecular ion (M+) peak at m/z = 425, which was 16 units (an oxygen atom) less than that of the 1:1:1:1 adduct of salicylaldehyde, Meldrum’s acid, cyclohexyl isocyanide and dimethyl acetylenedicarboxylate with the loss of a H2O and an acetone molecule. The 1H-NMR spectrum of 8a exhibited three single sharp lines arising from the two methoxy groups (at δ(H) 3.78 and 3.94 ppm) and the coumarin vinylic H atom (at 7.77). A fairly sharp doublet was seen at 6.83 (J = 8.2 Hz) for the amine NH group because of coupling with the CH of the cyclohexyl ring. Characteristic multiplets with appropriate chemical shifts and coupling constants for the eleven H-atoms of the cyclohexyl ring and the four H-atoms of the aromatic moiety were observed in the aliphatic and aromatic region of the spectrum, respectively. The 1H-decoupled 13C-NMR spectrum of 8a showed characteristic signals at δ(C) 24.5, 25.4 and 33.4 ppm (due to the methylenes of the cyclohexyl ring), 51.3 and 52.5 (for the two methoxy groups), and 51.5 (arising from the NCH moiety). A shielded resonance was observed at 88.8 (due to the NOC=C moiety) as well as five deshielded resonances

The product was isolated by suction filtration, washed successively with water (so as to maintain a neutral pH), and dried under vacuum. Yield: 74.07 %, C15H10NO2, Anal. Calcd. (%): C, 56.99; H, 3.19; N, 4.43, Found (%): C, 56.93; H, 3.22; N, 4.45, Melting point (M.p.): 141–143 oC, IR (KBr, v/cm-1): 3068, 2954, 1699, 1666, 1369, 1234, 779. UV-vis (DMF, nm): 343, 355.

The synthesis of the product: β-D-glucose pentaacetate is done though the acetylation using acetic anhydride with D-glucose with the help of sodium acetate. The recrystallization of the product is done though a polar solvent like water. The Result of this experiment has a percentage yield of 61% and analytical methods that are to detect the products are 1H NMR, 13 C NMR, COSY, FTIR (IR), Thin Layer Chromatography (TLC) and Melting point.

5,5-dimethyl-1,3-cyclohexanedione, or "dimedone" will be prepared using diethyl malonate and distilled mesityl oxide via carbonyl reactions such as Michaels addition and Claisen condensation reactions (Scheme 1).1 Also, the dimedone 13 exists in two forms: keto and enol forms. The form of dimedone will be influenced by the fast equilibrium between the dimedone and the solvent.2 As seen in the dimedone spectra in different concentration of solvent ( spectrum ), the keto-enol forms can be distinguished by comparing their the keto and enol CH3 peaks in the spectra. In addition, the derivatives of dimedone 19, hexahydroacridinedione, will be synthesized from the purified dimedone 13 and p-isopropylbenzaldehyde 14 and ammonium acetate in Scheme 2.

The reaction scheme is showed in Scheme 1. Briefly, using sulfamic acid as a catalyst, DHPMs1 and DHPMs2 were synthesized by ethanol thermal method. Urea (0.90 g, 15 mmol), acetaldehyde (0.44 g, 10 mmol) / benzaldehyde (1.06 g, 10 mmol), ethyl acetoacetate (1.56 g, 12 mmol) and sulfamic acid (0.8 g, 8 mmol) were dissolved in 10 mL ethanol to form a clear solution, which was settled in a 25 mL teflon-sealed autoclave and maintaining at 80 ºC for 2 h. After cooling, the reaction mixture was cleaned with cold water and 50 % ethanol, and the residue recrystallized from 95 % ethanol to afford the pure product. DHPMs1: Slightly water-soluble white powder; Yield = 1.31 g (71 %); Mp 192 - 193; formula: C9H14N2O3; FW: 198.22; IR (KBr) cm-1：3244, 3118, 2978, 1702, 1654；ESI-MS (m/z): 197.33 (M + H). DHPMs2: Slightly water-soluble white powder; Yield = 2.43 g (93.6 %); Mp 206 - 207; formula: C14H16N2O3; FW: 260.29; IR (KBr) cm-1：3235, 3108, 2975, 1702, 1645；ESI-MS (m/z): 259.18 (M +

(a) M. Katcka, Rocz. Chem. 1977, 51, 1455; (b) A. Reliquent, R. Besbes, F. Reliquent, J. C. Meslin, Synthesis., 1991, 7,

Attkins, R. C., & Carey, F. A. Organic Chemistry: A Brief Course; Mc Grawhill Inc.: New York, USA, 1990; p 205.

Dr. M. Pandeeswaran, Assistant Professor, Department of Chemistry, GTN Arts College, Dindigul – 624005, Tamilnadu, India.