(Z)-pent-3-en-2-one

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: To 4.0 g (0.03 mol) of o-chloroaniline in 50 ml of hydrochloric acid at 100° C. was added dropwise 3.4 g (0.04 mol) of 3-penten-2-one. The mixture was refluxed for 12 hours, then neutralised with 5N sodium hydroxide and extracted with dichloromethane. The organic extract was dried and concentrated to an oil. This was purified on a silica gel column to give 2.54 g (42% of the title product; m.p. 66°-68° C. Anal. Calcd. for C11H10NCl: C, 68.94; H, 5.26; N, 7.31; Cl, 18.50. Found C, 68.87; H, 5.27; N, 7.29; Cl, 18.48. The mixture was refluxed for 12 hours extracted with dichloromethane The organic extract was dried concentrated to an oil This was purified on a silica gel column

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

Procedure: To 4.0 g (0.03 mol) of o-chloroaniline in 50 ml of hydrochloric acid at 100° C. was added dropwise 3.4 g (0.04 mol) of 3-penten-2-one. The mixture was refluxed for 12 hours, then neutralised with 5N sodium hydroxide and extracted with dichloromethane. The organic extract was dried and concentrated to an oil. This was purified on a silica gel column to give 2.54 g (42% of the title product; m.p. 66°-68° C. Anal. Calcd. for C11H10NCl: C, 68.94; H, 5.26; N, 7.31; Cl, 18.50. Found C, 68.87; H, 5.27; N, 7.29; Cl, 18.48. The mixture was refluxed for 12 hours extracted with dichloromethane The organic extract was dried concentrated to an oil This was purified on a silica gel column

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

Procedure: Prepared according to general procedure A from 3-penten-2-one (68 μL, 0.70 mmol), cyclopentadiene (69 μL, 0.84 mmol), 70% aqueous perchloric acid (12.1 μL, 0.14 mmol) and (2S, 5S)-5-benzyl-3-methyl-2-(5-methyl-furan-2-yl)-imidazolidin-4-one (37.8 mg, 0.14 mmol) in water (175 μL) for 2.5 hours at 0° C. Purification by silica gel chromatography (9:1 pentane:ether) provided the title compound as a colorless oil in 85% yield (89 mg, 0.59 mmol); 14:1 endo:exo, endo 61% ee. IR (film) 3061, 2962, 2871, 1708,1461, 1426, 1359,1333, 1267, 1183, 1170,114, 1095, 1055,906.8, 797.8, 719.4, 654.5, 597.0 cm−1; 1H NMR (300 MHz, CDCl3) δ 6.21 (dd, J=6.0, 3.3 Hz, 1 H, CH═CH), 5.90 (dd, J=5.7, 2.7 Hz, 1H, CH═CH), 3.13 (m, 1H, CHCH═CH), 2.44 (m, 1H, CHCH═CH), 2.42 (dd, J=4.8, 3.9 Hz, 1H, CHCO), 2.10 (s, 3H, CH3CO), 1.86 (m, 1 H, CHCH3), 1.57 (m, 1H, C(H)H), 1.43 (m, 1H, C(H)H), 1.14 (d, J=6.9 Hz, 3H, CHCH3); 13C NMR (75 MHz, CDCl3) δ 209.2, 138.8, 132.6, 61.9, 49.3, 46.6, 46.5, 35.9, 29.5, 21.4; HRMS (CI) exact mass calc'd for (C10H14O) requires nm/z 150.1045, found m/z 150.1041. [α]D=+70.4 (c=1.0, CHCl3). Product ratios were determined by GLC analysis (120° C., 23 psi); (1R, 2R, 3S, 4R) endo isomer tr=6.9 min, and (1S, 2S, 3R, 4S) endo isomer tr=6.3 min, exo isomers tr=5.7, 5.5 min. Prepared Purification by silica gel chromatography (9:1 pentane:ether)

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

Procedure: To 4.0 g (0.03 mol) of o-chloroaniline in 50 ml of hydrochloric acid at 100° C. was added dropwise 3.4 g (0.04 mol) of 3-penten-2-one. The mixture was refluxed for 12 hours, then neutralised with 5N sodium hydroxide and extracted with dichloromethane. The organic extract was dried and concentrated to an oil. This was purified on a silica gel column to give 2.54 g (42% of the title product; m.p. 66°-68° C. Anal. Calcd. for C11H10NCl: C, 68.94; H, 5.26; N, 7.31; Cl, 18.50. Found C, 68.87; H, 5.27; N, 7.29; Cl, 18.48. The mixture was refluxed for 12 hours extracted with dichloromethane The organic extract was dried concentrated to an oil This was purified on a silica gel column

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

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

Procedure: In a three-necked flask were placed 33 g of o-aminophenol and 207 g of concentrated hydrochloric acid and the mixture was heated to the reflux temperature and stirred for 1 hour. To the mixture being heated under reflux was slowly added 51 g of 3-penten-2-one with a purity of 65% over 2 hours and stirring was continued for another 2 hours. Upon completion of the reaction, the reaction mixture was cooled to room temperature, 300 ml of a 48% aqueous solution of NaOH was added until the aqueous phase became alkaline. Ethyl acetate was added further, the organic layer was recovered and the solvent was distilled off under reduced pressure. The crude product thus obtained was purified by gas chromatography, recrystallized from hexane and the crystals collected by filtration were washed with hexane and dried at 80° C. under reduced pressure to give 18.9 g of 2,4-dimethyl-8-quinolinol. In a three-necked flask were placed To the mixture being heated under reflux over 2 hours stirring was continued for another 2 hours Upon completion of the reaction the organic layer was recovered the solvent was distilled off under reduced pressure The crude product thus obtained was purified by gas chromatography recrystallized from hexane the crystals collected by filtration were washed with hexane dried at 80° C. under reduced pressure

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

Procedure: A mixture of ethyl hydrazinoacetate hydrochloride (1.55 g, 10 mmol), 3-pentene-2-one (0.95 mL, 10 mmol) and sodium bicarbonate (1.00 g, 11.9 mmol) in ethanol (10 mL) was stirred at room temperature overnight. The reaction mixture was then filtered and concentrated under reduced pressure. The resulting oil was purified by medium pressure liquid chromatography on silica gel (0 to 100% gradient of ethyl acetate in hexanes as eluant) to provide the title compound as a yellow oil (0.26 g). The reaction mixture was then filtered concentrated under reduced pressure The resulting oil was purified by medium pressure liquid chromatography on silica gel (0 to 100% gradient of ethyl acetate in hexanes as eluant)

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

Procedure: 4,5-Dimethoxy-2-nitroaniline and 3-penten-2-one were subjected to a Skraup reaction. A black, tarry substance was obtained, from which an orange solid could be isolated by chromatography over silica gel using benzene-ethyl acetate (19:1) to elute the product. That material was thrice crystallized from 2-propanol, re-chromatographed, and again crystallized to afford 14% yield of golden 5,6-dimethoxy-2,4-dimethyl-8-nitroquinoline. Although it melted 85°-108°, it showed a single spot on two tlc systems. A black, tarry substance was obtained, from which an orange solid could be isolated by chromatography over silica gel to elute the product crystallized from 2-propanol re-chromatographed again crystallized

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

Procedure: 10 g of furfurylmercaptan and 15 g of 3-penten-2-one were dissolved in 100 ml of ethanol. The solution was stirred at room temperature for 48 hours. The solvent was then distilled off in vacuo at 50° C. The residue (18 g) was purified by preparative high pressure liquid chromatography (HPLC). 9 g of 4-[(furylmethyl)thio]-2-pentanone (purity 95%) were obtained. The IR, NMR and mass spectra of the compound agree with the structure described for it. The solvent was then distilled off in vacuo at 50° C The residue (18 g) was purified by preparative high pressure liquid chromatography (HPLC)

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

Procedure: A solution of 8.00 g pent-3-en-2-one in 50 mL dry diethyl ether was dropped to a solution of 73.5 mL of chloro[(trimethylsilyl)methyl]magnesium (1.0M in diethyl ether) and 955 mg of CuBr at −5° C. under Argon. The mixture was stirred for 1 hour at room temperature. An aqueous work-up followed by silica gel chromatography yielded 5.20 g (43%) of a colourless oil.