ethyl 2-diethoxyphosphorylbutanoate

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 solution of 11.8 g (46 mmol) of triethyl 2-phosphonobutyrate in 20 mL of tetrahydrofuran is added to a mixture of 1.8 g (46 mmol) of sodium hydride in 20 mL of tetrahydrofuran at 0° C. The reaction medium is stirred for 15 minutes. A solution of 3.4 g (20 mmol) of 3-ethoxy-4-hydroxybenzaldehyde prepared as in Example 32a in 20 mL of tetrahydrofuran is then added to the reaction mixture and the reaction medium is stirred at room temperature for 3 days. The reaction medium is then poured into saturated ammonium chloride solution, acidified with aqueous 2 N hydrochloric acid solution and extracted with ethyl acetate. The organic phases are combined, washed with water and dried over sodium sulfate. The solvent is evaporated off and the residue (12.5 g) is purified by chromatography on a column of silica eluted with an 80/20 heptane/ethyl acetate mixture. 3.7 g (71%) of ethyl 2-[1-(3-ethoxy-4-hydroxyphenyl)meth-(E)-ylidene]butyrate are obtained in the form of a yellow oil. is then added to the reaction mixture the reaction medium is stirred at room temperature for 3 days extracted with ethyl acetate washed with water dried over sodium sulfate The solvent is evaporated off the residue (12.5 g) is purified by chromatography on a column of silica eluted with an 80/20 heptane/ethyl acetate mixture

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

Procedure: A solution of 9 mL (37.8 mmol) of triethyl 2-phosphonobutyrate in 20 mL of tetrahydrofuran is added to a mixture of 1.52 g (37.8 mmol) of sodium hydride in 15 mL of tetrahydrofuran. The reaction medium is stirred for 20 minutes. A solution of 3.83 g (12.6 mmol) of 3-butoxy-4-iodobenzaldehyde (prepared as described in Example 19g) in 15 mL of tetrahydrofuran is then added to the reaction mixture and the reaction medium is stirred at room temperature for 2 hours 30 minutes. The reaction medium is poured into saturated ammonium chloride solution and extracted with ethyl acetate. The organic phases are combined, washed with saturated sodium chloride solution and dried over magnesium sulfate. The solvent is evaporated off and the residue (11.49 g) is purified by chromatography on silica gel eluted with a 95/5 heptane/ethyl acetate mixture. 4.90 g (97%) of ethyl 2-[1-(3-butoxy-4-iodophenyl)meth-(E)-ylidene]butyrate are obtained in the form of a yellow oil that crystallizes. the reaction medium is stirred at room temperature for 2 hours 30 minutes extracted with ethyl acetate washed with saturated sodium chloride solution dried over magnesium sulfate The solvent is evaporated off the residue (11.49 g) is purified by chromatography on silica gel eluted with a 95/5 heptane/ethyl acetate mixture

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

Procedure: 197 mg (4.9 mmol) of sodium hydride are added to a mixture of 1.2 mL (4.9 mmol) of triethyl 2-phosphonobutyrate and 415 mg of 3′-methylaminobiphenyl-4-carbaldehyde (2.0 mmol) in 10 mL of tetrahydrofuran. The reaction mixture is stirred at room temperature overnight, poured into saturated aqueous ammonium chloride solution and extracted with ethyl acetate. The organic phases are combined, washed with water and dried over sodium sulfate. The solvent is evaporated off and the residue (1.1 g) is purified by chromatography on a column of silica eluted with a 90/10 heptane/ethyl acetate mixture. 438 mg (72%) of ethyl 2-[1-(3′-methylaminobiphenyl-4-yl)meth-(E)-ylidene]butyrate are obtained in the form of off-white crystals. extracted with ethyl acetate washed with water dried over sodium sulfate The solvent is evaporated off the residue (1.1 g) is purified by chromatography on a column of silica eluted with a 90/10 heptane/ethyl acetate mixture

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

Procedure: 71.6 mg of lithium chloride was suspended in 5 ml of dry THF under an argon atmosphere, and 426 mg of ethyl 2-diethylphosphonobutanoate dissolved in 0.6 ml of dry THF was added thereto under stirring. The mixture was stirred at room temperature for 5 minutes, and then 323 mg of 1,8-diazabicyclo{5,4,0]-7-undecene (hereinafter referred to simply as DBU) was added thereto in the form of a 50° dry THF solution, and the mixture was stirred at room temperature for 10 minutes. Then, 450 mg of (4S,5R)-3-benzyloxycarbonyl-2,2-dimethyl-5-formyl-4-isobutyloxazolidine dissolved in 1.0 ml of dry THF was added thereto, and the mixture was stirred at room temperature overnight. The reaction solution was cooled to 0° C. and neutralized with 1N hydrochloric acid. Then, the solution was extracted three times with ethyl acetate. The organic layer was washed with water and with a saturated sodium chloride aqueous solution and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (n-hexane/ethyl acetate=10/1) to obtain 518 mg of ethyl 3-[(4S,5S)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]-2-ethyl-2-propenoate as colorless oily substance. was added The mixture was stirred at room temperature for 5 minutes was added was added the mixture was stirred at room temperature overnight Then, the solution was extracted three times with ethyl acetate The organic layer was washed with water and with a saturated sodium chloride aqueous solution dried over anhydrous sodium sulfate The solvent was distilled off under reduced pressure the residue was purified by silica gel column chromatography (n-hexane/ethyl acetate=10/1)

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 5.0 g (0.019 mol) of triethyl 2-phosphonobutyrate, 5.5 g (0.039 mol) of K2CO3, 6.2 g (0.076 mol) of 37% aqueous formaldehyde solution, and 15 mL of water was heated to about 80° C. for about 45 min. After cooling to RT, 75 mL of ether was added and the organic layer was separated, washed with brine (1×20 mL), dried (MgSO4), and filtered. The ether was carefully removed by distillation, leaving behind 2.1 g (87%) of the title compound as a clear oil which was used directly without further purification. 1H NMR (CDCl3): 67 1.01 (3H, t, J=7), 1.24 (3H, t, J=7), 2.26 (2H, q, J=7), 4.14 (2H, q, J=7), 5.45 (1H, s), 6.06 (1H, s). After cooling to RT the organic layer was separated washed with brine (1×20 mL) dried (MgSO4) filtered The ether was carefully removed by distillation

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

Procedure: 71.6 mg of lithium chloride was suspended in 5 ml of dry THF under an argon atmosphere, and 426 mg of ethyl 2-diethylphosphonobutanoate dissolved in 0.6 ml of dry THF was added thereto under stirring. The mixture was stirred at room temperature for 5 minutes, and then 323 mg of 1,8-diazabicyclo[5,4,0]-7-undecene (hereinafter referred to simply as DBU) was added thereto in the form of a 50: dry THF solution, and the mixture was stirred at room temperature for 10 minutes. Then, 450 mg of (4S,5R)-3-benzyloxycarbonyl-2,2-dimethyl-5-formyl-4-isobutyloxazolidine dissolved in 1.0 ml of dry THF was added thereto, and the mixture was stirred at room temperature overnight. The reaction solution was cooled to 0° C. and neutralized with 1N hydrochloric acid. Then, the solution was extracted three times with ethyl acetate. The organic layer was washed with water and with a saturated sodium chloride aqueous solution and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (n-hexane/ethyl acetate=10/1) to obtain 518 mg of ethyl 3-[(4S,5S)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]-2-ethyl-2-propenoate as colorless oily substance. was added The mixture was stirred at room temperature for 5 minutes was added was added the mixture was stirred at room temperature overnight Then, the solution was extracted three times with ethyl acetate The organic layer was washed with water and with a saturated sodium chloride aqueous solution dried over anhydrous sodium sulfate The solvent was distilled off under reduced pressure the residue was purified by silica gel column chromatography (n-hexane/ethyl acetate=10/1)

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

Procedure: 71.6 mg of lithium chloride was suspended in 5 ml of dry THF under an argon atmosphere, and 426 mg of ethyl 2-diethylphosphonobutanoate dissolved in 0.6 ml of dry THF was added thereto under stirring. The mixture was stirred at room temperature for 5 minutes, and then 323 mg of 1,8-diazabicyclo[5,4,0]-7-undecene (hereinafter referred to simply as DBU) was added thereto in the form of a 50% dry THF solution, and the mixture was stirred at room temperature for 10 minutes. Then, 450 mg of (4S,5R)-3-benzyloxycarbonyl-2,2-dimethyl-5-formyl-4-isobutyloxazolidine dissolved in 1.0 ml of dry THF was added thereto, and the mixture was stirred at room temperature overnight. The reaction solution was cooled to 0° C. and neutralized with 1N hydrochloric acid. Then, the solution was extracted three times with ethyl acetate. The organic layer was washed with water and with a saturated sodium chloride aqueous solution and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (n-hexane/ethyl acetate=10/1) to obtain 518 mg of ethyl 3-[(4S,5S)-3-benzyloxycarbonyl-2,2-dimethyl-4-isobutyloxazolidin-5-yl]-2-ethyl-2-propenoate as colorless oily substance. was added The mixture was stirred at room temperature for 5 minutes was added was added the mixture was stirred at room temperature overnight Then, the solution was extracted three times with ethyl acetate The organic layer was washed with water and with a saturated sodium chloride aqueous solution dried over anhydrous sodium sulfate The solvent was distilled off under reduced pressure the residue was purified by silica gel column chromatography (n-hexane/ethyl acetate=10/1)

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 5.0 g (0.019 mol) of triethyl 2-phosphonobutyrate, 5.5 g (0.039 mol) of K2CO3, 6.2 g (0.076 mol) of 37% aqueous formaldehyde solution, and 15 mL of water was heated to about 80° C. for about 45 min. After cooling to RT, 75 mL of ether was added and the organic layer was separated, washed with brine (1×20 mL), dried (MgSO4), and filtered. The ether was carefully removed by distillation, leaving behind 2.1 g (87%) of the title compound as a clear oil which was used directly without further purification. 1H NMR (CDCl3): δ 1.01 (3 H, t, J=7), 1.24 (3 H, t, J=7), 2.26 (2 H, q, J=7), 4.14 (2 H, q, J=7), 5.45 (1 H, s), 6.06 (1 H, s). After cooling to RT the organic layer was separated washed with brine (1×20 mL) dried (MgSO4) filtered The ether was carefully removed by distillation

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

Procedure: In analogy to the procedure given in Example 1: Triethyl 2-phosphonobutyrate was reacted with retinal to give ethyl 5,9-dimethyl-2-ethyl-11-(2,6,6-trimethyl-1cyclohexen-1-yl)-2,4,6,8,10-undecapentaenoate, which was converted by the procedure of Example 2 to 5,9-dimethyl-2-ethyl-11-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2,4,6,8,10-undecapentaenoic acid, m.p.=164°-165° C.

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

Procedure: A solution of 11.8 g (46 mmol) of triethyl 2-phosphonobutyrate in 20 mL of tetrahydrofuran is added to a mixture of 1.8 g (46 mmol) of sodium hydride in 20 mL of tetrahydrofuran at 0° C. The reaction medium is stirred for 15 minutes. A solution of 3.4 g (20 mmol) of 3-ethoxy-4-hydroxybenzaldehyde prepared as in Example 32a in 20 mL of tetrahydrofuran is then added to the reaction mixture and the reaction medium is stirred at room temperature for 3 days. The reaction medium is then poured into saturated ammonium chloride solution, acidified with aqueous 2 N hydrochloric acid solution and extracted with ethyl acetate. The organic phases are combined, washed with water and dried over sodium sulfate. The solvent is evaporated off and the residue (12.5 g) is purified by chromatography on a column of silica eluted with an 80/20 heptane/ethyl acetate mixture. 3.7 g (71%) of ethyl 2-[1-(3-ethoxy-4-hydroxyphenyl)meth-(E)-ylidene]butyrate are obtained in the form of a yellow oil. is then added to the reaction mixture the reaction medium is stirred at room temperature for 3 days extracted with ethyl acetate washed with water dried over sodium sulfate The solvent is evaporated off the residue (12.5 g) is purified by chromatography on a column of silica eluted with an 80/20 heptane/ethyl acetate mixture