5,5-dimethylhexanoic acid

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 3.0 g. of 5,5-dimethylhexanoic acid (23.0 mmol.) and 2.5 ml. of thionyl chloride (34.3 mmol.) was allowed to stand at room temperature for 16 hours. Upon addition of 20 ml. of Skellysolve B, the resulting solution was refluxed for 1 hour, then the solvent was removed in vacuo. The remaining residue was azeotroped twice with Skellysolve B to yield a pale yellow liquid which was added dropwise to a suspension of 3.0 g. of 4-(4-chlorophenyl)-2-(hydroxymethyl)-5H-pyrido[3,4-b][1,4]benzothiazin-3(2H)-one (8.4 mmol.) in 30 ml. of cold pyridine. After stirring in an ice-bath for 35 minutes, the reaction mixture was poured onto ice-water resulting in the formation of a solid product which was filtered, washed with water, and purified using flash chromotography on silica gel, using a mixture of 5% ethyl acetate: 95% methylene chloride as the eluent. Fractions containing product were combined and triturated with diethyl ether to yield 4 -(4-chlorophenyl)-2-[(5,5-dimethyl-1-oxohexyloxy)methyl]-5H-pyrido[3,4-b][1,4]-benzothiazin-3(2H)-one as a yellow solid (2.4 g; 59% yield) having the structural formula, ##STR15## a melting point in the range of 143°-145° C. and the following elemental analysis: A mixture of 3.0 g Upon addition of 20 ml the solvent was removed in vacuo The remaining residue was azeotroped twice with Skellysolve B to yield a pale yellow liquid which was added dropwise to a suspension of 3.0 g the reaction mixture was poured onto ice-water resulting in the formation of a solid product which was filtered washed with water purified a mixture of 5% ethyl acetate Fractions containing product triturated with diethyl ether

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 3.0 g. of 5,5-dimethylhexanoic acid (23.0 mmol.) and 2.5 ml. of thionyl chloride (34.3 mmol.) was allowed to stand at room temperature for 16 hours. Upon addition of 20 ml. of Skellysolve B, the resulting solution was refluxed for 1 hour, then the solvent was removed in vacuo. The remaining residue was azeotroped twice with Skellysolve B to yield a pale yellow liquid which was added dropwise to a suspension of 3.0 g. of 4-(4-chlorophenyl)-2-(hydroxymethyl)-5H-pyrido[3,4-b][1,4]benzothiazin-3(2H)-one (8.4 mmol.) in 30 ml. of cold pyridine. After stirring in an ice-bath for 35 minutes, the reaction mixture was poured onto ice-water resulting in the formation of a solid product which was filtered, washed with water, and purified using flash chromotography on silica gel, using a mixture of 5% ethyl acetate: 95% methylene chloride as the eluent. Fractions containing product were combined and triturated with diethyl ether to yield 4 -(4-chlorophenyl)-2-[(5,5-dimethyl-1-oxohexyloxy)methyl]-5H-pyrido[3,4-b][1,4]-benzothiazin-3(2H)-one as a yellow solid (2.4 g; 59% yield) having the structural formula, ##STR15## a melting point in the range of 143°-145° C. and the following elemental analysis: A mixture of 3.0 g Upon addition of 20 ml the solvent was removed in vacuo The remaining residue was azeotroped twice with Skellysolve B to yield a pale yellow liquid which was added dropwise to a suspension of 3.0 g the reaction mixture was poured onto ice-water resulting in the formation of a solid product which was filtered washed with water purified a mixture of 5% ethyl acetate Fractions containing product triturated with diethyl ether

Conditions: temp:135.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 500 mL, 4 neck round bottom flask equipped with mechanical stirring, a nitrogen inlet, a thermometer, a condenser and an addition funnel was charged with 60% sodium hydride in mineral oil (20.5 g. 0.51 mol), methyl neo-octanoate (92.3 g., 0.58 mol, prepared from neo-octanoic acid, a product of Exxon), and xylene (42.8 g.). The mixture was heated to reflux (135° C.), and then a solution of acetophenone (32.4 g. 0.27 mol) in xylene (19.1 g.) was added over 1.25 h. The mixture was kept at reflux for an additional 1 h. After cooling to room temperature, the reaction was quenched by the careful addition of methanol (20 mL), and then acidified with 150 g/L sulfuric acid (180 mL). After separation of layers, the organic phase was washed with water (2×100 mL) and brine (100 mL). After drying by passing through anhydrous sodium sulfate, the solution was concentrated in vacuo at 70° C. down to 12 mbar to yield an orange liquid containing product in a crude yield of 63%. Vacuum distillation (200 mtorr) through a 15 cm Vigreux column yielded the product in the heart cut: 1-phenyl-3-neoheptyl-1,3-propanedione (X) (37.2 g., 96% pure, 0.14 mol; 53% yield; bp: 94-135° C.). Dypnone, the self-condensation product of acetophenone was undetectable in the product. A 500 mL, 4 neck round bottom flask equipped with mechanical stirring, a nitrogen inlet The mixture was heated at reflux for an additional 1 h After cooling to room temperature the reaction was quenched by the careful addition of methanol (20 mL) After separation of layers the organic phase was washed with water (2×100 mL) and brine (100 mL) After drying the solution was concentrated in vacuo at 70° C. down to 12 mbar to yield an orange liquid containing product in a crude yield of 63% Vacuum distillation (200 mtorr) through a 15 cm Vigreux column yielded the product in the heart cut

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 3.0 g. of 5,5-dimethylhexanoic acid (23.0 mmol.) and 2.5 ml. of thionyl chloride (34.3 mmol.) was allowed to stand at room temperature for 16 hours. Upon addition of 20 ml. of Skellysolve B, the resulting solution was refluxed for 1 hour, then the solvent was removed in vacuo. The remaining residue was azeotroped twice with Skellysolve B to yield a pale yellow liquid which was added dropwise to a suspension of 3.0 g. of 4-(4-chlorophenyl)-2-(hydroxymethyl)-5H-pyrido[3,4-b][1,4]benzothiazin-3(2H)-one (8.4 mmol.) in 30 ml. of cold pyridine. After stirring in an ice-bath for 35 minutes, the reaction mixture was poured onto ice-water resulting in the formation of a solid product which was filtered, washed with water, and purified using flash chromotography on silica gel, using a mixture of 5% ethyl acetate: 95% methylene chloride as the eluent. Fractions containing product were combined and triturated with diethyl ether to yield 4 -(4-chlorophenyl)-2-[(5,5-dimethyl-1-oxohexyloxy)methyl]-5H-pyrido[3,4-b][1,4]-benzothiazin-3(2H)-one as a yellow solid (2.4 g; 59% yield) having the structural formula, ##STR15## a melting point in the range of 143°-145° C. and the following elemental analysis: A mixture of 3.0 g Upon addition of 20 ml the solvent was removed in vacuo The remaining residue was azeotroped twice with Skellysolve B to yield a pale yellow liquid which was added dropwise to a suspension of 3.0 g the reaction mixture was poured onto ice-water resulting in the formation of a solid product which was filtered washed with water purified a mixture of 5% ethyl acetate Fractions containing product triturated with diethyl ether