tripropan-2-yl phosphite

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:

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:

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

Conditions: temp:125.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 500 mL three-neck flask was charged with the crude chloromethylether 1 (317 g, 2.00 mol). Triisopropylphosphite (494 mL) was added dropwise through an additional funnel while heating in a 125° C. oil bath and stirring vigorously. Collect 2-chloropropane distillate via short-path head in a dry ice cooled receiver, argon blanket, collected 140 g distillate (theoretical 157 g). Phosphite blanched reaction to yellow, continue heating another 2 h at 125° C. oil bath, then arrange for vacuum distillation using a vacuum pump. Distilled a yellow front cut (140 g, head to 135° C., bottom to 190° C.), then changed to clean receiver. Main fraction was collected at head temperature of 178-187° C. (mostly 185-187° C.) with vacuum unknown at bath temperature of 222-228° C. 258 g of the product 2 was given (47% yield from 1,3-dioxolane). Collect 2-chloropropane distillate via short-path head in a dry ice cooled receiver, argon blanket, collected 140 g distillate (theoretical 157 g) reaction to yellow, continue heating another 2 h at 125° C. oil bath arrange for vacuum distillation Distilled a yellow front cut (140 g, head to 135° C., bottom to 190° C.) Main fraction was collected at head temperature of 178-187° C. (mostly 185-187° C.) with vacuum unknown at bath temperature of 222-228° C

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

Procedure: 11.1 g (27.9 mmol) of benzyl 6-acetoxy-4-bromomethyl-2-formylamino-hex-3-enoate and 30.5 ml (111.5 mmol) of 90% triisopropyl phosphite are heated to 80° C. and the mixture is stirred for 18 hours under a pressure of 100-150 mbar. Excess triisopropyl phosphite is removed by distillation and the residue is purified by chromatography over silica gel with ethyl acetate/isopropanol (7:1), giving benzyl 6-acetoxy-2-formylamino-4-diisopropylphosphonomethyl-hex-3-enoate as an orange oil. Excess triisopropyl phosphite is removed by distillation the residue is purified by chromatography over silica gel with ethyl acetate/isopropanol (7:1)

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

Procedure: 21.2 g (63.1 mmol) of ethyl 6-acetoxy-4-bromomethyl-2(R)-formylamino-hex-3-enoate and 69.1 ml (252.2 mmol) of 90% triisopropyl phosphite are heated to 80° C. and the mixture is stirred for 18 hours under a pressure of 100-150 mbar. Excess triisopropyl phosphite is removed by distillation and the residue is purified by flash chromatography on silica gel with ethyl acetate/ethanol (19:1), giving 8.6 g of ethyl 6-acetoxy-2(R)-formylamino-4-diisopropylphosphonomethyl-hex-3-enoate a yellowish-orange oil. ee=92.5%; αD -90.2°±0.4°, (c=2.84 CH2Cl2). Excess triisopropyl phosphite is removed by distillation the residue is purified by flash chromatography on silica gel with ethyl acetate/ethanol (19:1)