tert-butyl 2-(1,3-dioxoisoindol-2-yl)oxyacetate

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 N-hydroxyphthalimide (10 g, 61.3 mmol), K2CO3 (16.9 g, 122 mmol) and tert-butyl bromoacetate (12 g, 9 mL, 61.3 mmol) in DMF (60 mL) was stirred at room temperature for 3 hours and the solvent was evaporated under high vacuum. The residue was dissolved in EtOAc, washed with brine, dried over Na2SO4 and filtered. The residue after evaporation of the solvent was recrystallized from a mixture of CH2Cl2/EtOAc/hexane to give the title compound (12 g, 71% yield) as a white solid. Mp 140-141° C. 1H NMR (300 MHz, CDCl3) δ 7.80-7.90 (m, 2H), 7.74-7.77 (m, 2H), 4.71 (s, 2H), 1.49 (s, 9H). 13C NMR (75 MHz, CDCl3) δ 166.0, 163.0, 134.7, 128.9, 123.7, 83.0, 73.5, 28.1. Mass spectrum (API-TIS) m/z 278 (MH−), 295 (MNH4+). Anal. calcd. for C14H15NO5: C, 60.64; H, 5.45; N, 5.05. Found C, 60.47; H, 5.31; N, 4.96. the solvent was evaporated under high vacuum The residue was dissolved in EtOAc washed with brine dried over Na2SO4 filtered The residue after evaporation of the solvent was recrystallized from a mixture of CH2Cl2/EtOAc/hexane

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

Procedure: In 1.35 l of dichloromethane is dissolved 37.4 g (0.135 mole) of N-(tert-butoxycarbonylmethoxy) phthalimide, and 9.21 ml (0.189 mole) of hydrazine hydrate is added dropwise to the solution over the period of 10 minutes, followed by stirring at room temperature for 2 hours. 3.95 ml (0.081 mole) of hydrazine hydrate is furthermore added, followed by stirring for further 1.5 hours. The reaction solution is filtered, and the filtrate is washed with 300 ml of 2N ammonium water and aqueous sodium chloride solution successively, and dried over anhydrous sodium sulfate. The solvent is distilled off under reduced pressure to give 18.95 g (95.4%) of O-(tert-butoxycarbonylmethyl)hydroxylamine as a yellow oily product. is added dropwise to the solution over the period of 10 minutes by stirring for further 1.5 hours The reaction solution is filtered the filtrate is washed with 300 ml of 2N ammonium water and aqueous sodium chloride solution successively dried over anhydrous sodium sulfate The solvent is distilled off under reduced pressure

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

Procedure: In N,N-dimethylformamide (200 ml) ar dissolved 24.5 g (0.15 mole) of N-hydroxyphthalimide and 29.3 g (0.15 mole) of tert-butyl bromoacetate, and 20.7 g (0.15 mole) of powdered potassium carbonate is added to the solution under ice-cooling with stirring. The reaction solution is stirred under ice-cooling for 30 minutes and then at room temperature for 20 hours, and poured into 2 l of ice cold water. The crystals that separate out are recovered by filtration, washed with 1 l of water and 500 ml of hexane successively and dried under reduced pressure at 40° C. to give 39.7 g (95.5%) of N-(tert-butoxycarbonylmethoxy)phthalimide as colorless crystals. This product is to be used in the subsequent reaction, and part of this product, when recrystallized from etyyl acetate-n-hexane (1:2), exhibits a melting point of 145°-146° C. is added to the solution under ice- cooling The reaction solution is stirred under ice- cooling for 30 minutes The crystals that separate out are recovered by filtration washed with 1 l of water and 500 ml of hexane successively dried under reduced pressure at 40° C.

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

Procedure: t-Butyl chloroacetate (13.0 g, prepared according to Org. Synth., Coll. Vol. 4, 263) was added dropwise to a stirred mixture of N-hydroxyphthalimide (14.2 g), triethylamine (23.0 g), and dimethylformamide (30 ml), and the resulting mixture was stirred for 4 hr. The mixture was poured into water (500 ml), and the precipitated solid was collected, washed with water, and dried. Recrystallisation from ethanol gave N-t-butoxycarbonylmethoxyphthalimide (17.26 g, 72%); m.p. 145.6°; τ values (DMSO-d6) 2.09 (4 Ar-H), 5.28 (CH2), 8.56 (But). the precipitated solid was collected washed with water dried Recrystallisation from ethanol

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

Procedure: t-Butyl chloroacetate (13.0 g, prepared according to Org. Synth., Coll. Vol. 4, 263) was added dropwise to a stirred mixture of N-hydroxyphthalimide (14.2 g), triethylamine (23.0 g), and dimethylformamide (30 ml), and the resulting mixture was stirred for 4 hr. The mixture was poured into water (500 ml), and the precipitated solid was collected, washed with water, and dried. Recrystallisation from ethanol gave N-t-butoxycarbonylmethoxyphthalimide (17.26 g. 72%); m.p. 145.6°; τ values (DMSO-d6) 2.09 (4 Ar--H), 5.28 (CH2), 8.56 (But). the precipitated solid was collected washed with water dried Recrystallisation from ethanol

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

Procedure: A solution of N-t-butoxycarbonylmethoxyphthalimide (21g) in methylene chloride (250ml) was treated with 100% hydrazine hydrate (7.6ml) in methanol (15ml), and the mixture was stirred for 1.5 hr. 5N-Ammonia solution was added to dissolve the precipitated solid. The organic layer was separated, and the aqueous layer was further extracted with methylene chloride. The combined extracts were washed with water, dried, and evaporated to give a pale-yellow solid. To this was added ether, the mixture was filtered, and the filtrate evaporated to give t-butoxycarbonylmethoxyamine as a pale yellow liquid, (8.88g, 80%); νmax. (Nujol) includes 3330, 3260 cm.-1 (NH2), 1742 cm.-1 (-COOBut); τ values (DMSO-d6) are 3.75 (-NH2), 5.96 (CH2) 8.55 (But). to dissolve the precipitated solid The organic layer was separated the aqueous layer was further extracted with methylene chloride The combined extracts were washed with water dried evaporated to give a pale-yellow solid the mixture was filtered the filtrate evaporated

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

Procedure: t-Butyl chloroacetate (13.0g, prepared according to Org. Synth., Coll.Vol. 4, 263) was added dropwise to a stirred mixture of N-hydroxyphthalimide (14.2g), triethylamine (23.0g), and dimethylformamide (30ml), and the resulting mixture was stirred for 4 hr. The mixture was poured into water (500 ml), and the precipitated solid was collected, washed with water, and dried. Recrystallisation from ethanol gave N-t-butoxycarbonylmethoxyphthalimide (17.26g, 72%); m.p. 145.6°; τ values (DMSO-d6) 2.09 (4 Ar-H), 5.28 (CH2), 8.56 (But). the precipitated solid was collected washed with water dried Recrystallisation from ethanol

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

Procedure: t-Butyl chloroacetate (13.0 g, prepared according to Org. Synth., Coll. Vol. 4, 263) was added dropwise to a stirred mixture of N-hydroxyphthalimide (14.2 g), triethylamine (23.0 g), and dimethylformamide (30 ml), and the resulting mixture was stirred for 4 hr. The mixture was poured into water (500 ml), and the precipitated solid was collected, washed with water, and dried. Recrystallisation from ethanol gave N-t-butoxycarbonylmethoxyphthalimide (17.26 g, 72%); m.p. 145.6°; τ values (DMSO-d6) 2.09 (4 Ar-H), 5.28 (CH2), 8.56 (But). the precipitated solid was collected washed with water dried Recrystallisation from ethanol

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

Procedure: t-Butyl chloroacetate (13.0 g, prepared according to Org. Synth., Coll. Vol. 4, 263) was added dropwise to a stirred mixture of N-hydroxyphthalimide (14.2 g), triethylamine (23.0 g), and dimethylformamide (30 ml), and the resulting mixture was stirred for 4 hr. The mixture was poured into water (500 ml), and the precipitated solid was collected, washed with water, and dried. Recrystallisation from ethanol gave N-t-butoxycarbonylmethoxyphthalimide (17.26 g, 72%); m.p. 145.6°; τ values (DMSO-d6) 2.09 (4 Ar-H), 5.28 (CH2), 8.56 (But). the precipitated solid was collected washed with water dried Recrystallisation from ethanol

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

Procedure: t-Butyl chloroacetate (13.0g, prepared according to Org. Synth., Coll. Vol. 4, 263) was added dropwise to a stirred mixture of N-hydroxyphthalimide (14.2g), triethylamine (23.0g), and dimethylformamide (30ml), and the resulting mixture was stirred for 4 hr. The mixture was poured into water (500 ml), and the precipitated solid was collected, washed with water, and dried. Recrystallisation from ethanol gave N-t-butoxycarbonylmethoxyphthalimide (17.26g, 72%); m.p. 145.6°; τ values (DMSO-d 6) 2.09 (4 Ar-H), 5.28 (CH2), 8.56 (But). the precipitated solid was collected washed with water dried Recrystallisation from ethanol