5,5-dimethylhexane-2,4-dione

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: Similarly, reaction of 5,5-dimethyl-2,4-hexanedione, benzaldehyde and ammonium hydroxide by the procedure of Example 6 with separation of the 1,4-dihydropyridines thus obtained and subsequent treatment with ethyl chloroformate as described above gives 3,5-di-t-butylcarbonyl-1-carbethoxy-1,4-dihydro-2,6-dimethyl-4-phenylpyridine and 3,5-diacetyl-2,6-di-t-butyl-1-carbethoxy-1,4-dihydro-4-phenylpyridine. with separation of the 1,4-dihydropyridines thus obtained

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

Procedure: Similarly, reaction of 5,5-dimethyl-2,4-hexanedione, benzaldehyde and ammonium hydroxide by the procedure of Example 6 with separation of the 1,4-dihydropyridines thus obtained and subsequent treatment with ethyl chloroformate as described above gives 3,5-di-t-butylcarbonyl-1-carbethoxy-1,4-dihydro-2,6-dimethyl-4-phenylpyridine and 3,5-diacetyl-2,6-di-t-butyl-1-carbethoxy-1,4-dihydro-4-phenylpyridine. with separation of the 1,4-dihydropyridines thus obtained

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

Procedure: To a solution of 5.00 g (35.16 mmol) 2,2-dimethyl-3,5-hexanedione in 20 mL of toluene loaded with 10.00 g of sodium sulfate was added 5.14 g (70.32 mmol) sec-butylamine. The mixture was refluxed 3 days. 4.90 g of light yellow oil was obtained after work-up. The isolated yield was 71%. 1H NMR (500 MHz, C6D6): δ=11.52 (s, 1H), 5.18 (s, 1H), 2.95 (m, 1H), 1.51 (s, 3H), 1.31 (s, 9H), 1.14 (s, 2H), 0.80 (d, 3H), 0.67 (t, 3H). The mixture was refluxed 3 days

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

Procedure: To a solution of 5.00 g (35.16 mmol) 2,2-dimethyl-3,5-hexanedione in 20 mL of toluene loaded with 10.00 g of sodium sulfate was added 5.14 g (70.32 mmol) sec-butylamine. The mixture was refluxed 3 days. 4.90 g of light yellow oil was obtained after work-up. The isolated yield was 71%. 1H NMR (500 MHz, C6D6): δ=11.52 (s, 1H), 5.18 (s, 1H), 2.95 (m, 1H), 1.51 (s, 3H), 1.31 (s, 9H), 1.14 (s, 2H), 0.80 (d, 3H), 0.67 (t, 3H). The mixture was refluxed 3 days

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

Procedure: To a solution of 15.00 g (105.49 mmol) 2,2-dimethyl-3,5-hexanedione in 50 mL of toluene loaded with 30.00 g sodium sulfate was added 12.47 g (210.97 mmol) isopropylamine. The mixture was refluxed for 4 days. Removal of toluene resulted in a yellow oil, which was subjected to vacuum transfer at 80° C. under 125 mTorr. 16.5 g of clear oil was obtained with a yield of 84%. 1H NMR (500 MHz, C6D6): δ=11.50 (s, 1H), 5.16 (s, 1H), 3.11 (m, 1H), 1.49 (s, 3H), 1.31 (s, 9H), 0.79 (d, 6H). The mixture was refluxed for 4 days Removal of toluene resulted in a yellow oil, which was subjected to vacuum transfer at 80° C. under 125

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

Procedure: Methyl t-butyl ketone was condensed with ethyl acetate in the presence of sodamide to yield 5,5-dimethyl-2,4-hexanedione. This material was reacted with phosphorus pentachloride to yield the divinyl chloride, which was in turn dehydrohalogenated with sodamide to give 5,5-dimethyl-1,3-hexadiyne. This alkyne was then dimerized using the procedure of Hay (see e.g. Hay, A. S., J. Org. Chem. 27, 3320 (1962)), using copper(I) chloride-tetramethylethylenediamine (TMEDA) complex as the catalyst, to yield the desired t-butyl endcapped tetrayne. The tetrayne melted at 99° C. and decomposed between 130° C. and 140° C. It is also stable to moderate pressures; exposure to 40 kbar pressure for one hour caused no changes in the IR spectrum, and at 60 kbar only about 2% graphitization was seen.

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

Procedure: By a similar procedure as described in Example 1 using 1-(4-iodophenyl)-butane-1,3-dione (prepared by reaction of 4-iodoacetophenone with ethyl acetate in the presence of sodium hydride) in place of 5,5-dimethylhexane-2,4-dione, (E)-5-(4-hydroxy-3-methoxyphenyl)-1-(4-iodophenyl)-pent-4-ene-1,3-dione (0.40 g, 0.95 mmol, 31%) was obtained as a yellow solid: mp 139-141° C.; 1H NMR (400 MHz; CDCl3) δ 3.95 (3H, s, OCH3), 5.87 (1H, s, OH), 6.27 (1H, s, H-2), 6.42 (1H, d, J=16.0 Hz, H-4), 6.87 (1H, d, J=8.4 Hz, H-5′), 6.99 (1H, s, H-2′), 7.06 (1H, d, J=8.4 Hz, H-6′), 7.54-7.60 (3H, m, H-5, H-3″, H-5″), 7.41-7.62 (2H, m, H-2″, H-6″), 16.18 (1H, s, OH) ppm; 13C NMR (100 MHz; CDCl3) δ 187.5, 180.8, 148.1, 146.9, 140.9, 138.0, 135.5, 128.9, 127.6, 123.2, 120.9, 115.1, 109.6, 100.0, 97.1, 56.0 ppm.

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

Procedure: By a similar procedure as described in Example 1 using 1-(4-iodophenyl)-butane-1,3-dione (prepared by reaction of 4-iodoacetophenone with ethyl acetate in the presence of sodium hydride) in place of 5,5-dimethylhexane-2,4-dione, (E)-5-(4-hydroxy-3-methoxyphenyl)-1-(4-iodophenyl)-pent-4-ene-1,3-dione (0.40 g, 0.95 mmol, 31%) was obtained as a yellow solid: mp 139-141° C.; 1H NMR (400 MHz; CDCl3) δ 3.95 (3H, s, OCH3), 5.87 (1H, s, OH), 6.27 (1H, s, H-2), 6.42 (1H, d, J=16.0 Hz, H-4), 6.87 (1H, d, J=8.4 Hz, H-5′), 6.99 (1H, s, H-2′), 7.06 (1H, d, J=8.4 Hz, H-6′), 7.54-7.60 (3H, m, H-5, H-3″, H-5″), 7.41-7.62 (2H, m, H-2″, H-6″), 16.18 (1H, s, OH) ppm; 13C NMR (100 MHz; CDCl3) δ 187.5, 180.8, 148.1, 146.9, 140.9, 138.0, 135.5, 128.9, 127.6, 123.2, 120.9, 115.1, 109.6, 100.0, 97.1, 56.0 ppm.

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

Procedure: By a similar procedure as described in Example 1 using 1-(4-hydroxy-3-methoxyphenyl)-butane-1,3-dione (prepared by reaction of 4-hydroxy-3-methoxyacetophenone with ethyl acetate in the presence of sodium hydride) in place of 5,5-dimethylhexane-2,4-dione, (E)-1,5-bis-(4-hydroxy-3-methoxyphenyl)-pent-4-ene-1,3-dione (920 mg, 39%) was obtained as yellow needles: mp 170-172° C.; LRMS m/z 342 (M+); 1H NMR (500 MHz, CDCl3) δ 3.95 (3H, s, OCH3), 3.98 (3H, s, OCH3), 5.85 (1H, brs, OH), 6.04 (1H, brs, OH), 6.26 (1H, s, H-2), 6.48 (1H, d, J=15.7 Hz, H-4), 6.94 (1H, d, J=7.2 Hz, H-5″), 6.97 (1H, d, J=8.3 Hz, H-5′), 7.05 (1H, brs, H-2″), 7.12 (1H, brd, J=8.3 Hz, H-6″), 7.51 (1H, brd, J=7.2 Hz, H-6′), 7.56 (1H, brs, H-2′), 7.60 (1H, J=15.7 Hz, H-5), 16.2 (1H, brs, OH) ppm; TLC Rf=0.5 (silica, dichloromethane); HPLC Rt 14 min 99.6% purity.

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

Procedure: Chlorotrimethylsilane (26.8 ml, 0.21 mol) was added dropwise to a stirred pale yellow solution of tetrabutylammonium bromide (1.139, 3.50 mmol) in dry acetonitrile (100 ml) at room temperature under nitrogen. The resulting solution was cooled in ice and 5,5-dimethylhexane-2,4-dione (10.0 g, 70.4 mmol) and then dry dimethylsulphoxide (14.7 ml, 0.21 mol) were added dropwise over 5 minutes producing a yellow solution which was allowed to warm slowly to room temperature with stirring over 3 hours. The mixture was diluted with water (1000 ml) and stirred for 10 min and then extracted with ether (1×500 ml, 2×250 ml). The combined ether layers were dried over magnesium sulphate, filtered and concentrated under reduced pressure to leave a yellow oil. The crude product was purified by distillation under reduced pressure to provide the title compound (10.0 g) as a pale yellow oil, b.p. 220-225° C./60 mmHg. The resulting solution was cooled in ice producing a yellow solution which stirred for 10 min extracted with ether (1×500 ml, 2×250 ml) The combined ether layers were dried over magnesium sulphate filtered concentrated under reduced pressure to leave a yellow oil The crude product was purified by distillation under reduced pressure