2-(bromomethyl)-6-methylbenzoyl bromide

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:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 10.0 g (86 mmol) of cis-1,3-cyclohexanediol were taken up in 150 ml of methyl tert-butyl ether (MTBE), admixed at approx. 20° C. with 6.72 g (59.9 mmol) of potassium tert-butoxide (KOtBu) and stirred. After about 30 minutes, the suspension was cooled to 5° C. and admixed dropwise with 7.4 g (approx. 50%) of methyl 2-bromomethyl-6-methylbenzoate, which may be prepared, for example, by methanolyzing the acid bromide (2-bromomethyl-6-methylbenzoyl bromide) or by brominating methyl 2,6-dimethylbenzoate. The mixture was stirred at 0–5° C. for 1 h, heated to 20–23° C. and left to stir overnight. Water was added, the mixture was stirred vigorously, the phases were separated, the organic phase was washed once more with water and then the organic phase was concentrated under reduced pressure. The residue (4.6 g) was chromatographed on silica gel (1:1 ethyl acetate/n-heptane). 1.2 g of the desired compound were obtained as a light yellow oil, 1H NMR (CDCl3), δ =1.27 (m, 1H), 1.45 (m, 1H), 1.55 (m, 1H), 1.74 (m, 1H), 1.82 (m, 1H), 2.05 (m, 1H), 2.34 (s, 3H), 3.46 (m, 1H), 3.72 (m, 1H), 3.91 (s, 3H), 4.58 (dd, 2H), 7.15 (d, 1H), 7.20 (d, 2H), 7:27 (m, 1H). The mixture was stirred at 0–5° C. for 1 h heated to 20–23° C. left to stir overnight the mixture was stirred vigorously the phases were separated the organic phase was washed once more with water the organic phase was concentrated under reduced pressure The residue (4.6 g) was chromatographed on silica gel (1:1 ethyl acetate/n-heptane)

Conditions: temp:-5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 500 g (4.3 mol) of cis-1,3-cyclohexanediol were dissolved in 5 l of NMP and admixed with 336 g (3.0 mol) of potassium tert-butoxide (KOtBu). The internal temperature rose to 28° C. The mixture was stirred for 30 min, then cooled to −5° C. and admixed dropwise with 370 g (approx. 94%, approx. 1.4 mol) of methyl 2-bromomethyl-6-methylbenzoate which may be prepared, for example, by methanolyzing 2-bromomethyl-6-methylbenzoyl bromide or by brominating methyl 2,6-dimethylbenzoate. The mixture was stirred for 30 min and then diluted with 5 l of water. After washing three times with 3 l of n-heptane each time and discarding the n-heptane solutions, the remaining aqueous phase was extracted four times with 2.5 l of MTBE each time. The combined MTBE phases were washed once with 5 l of water, dried over Na2SO4 and subsequently concentrated by evaporation under reduced pressure. 234 g of the desired compound were obtained as a yellowish oil and were used in the next reaction (for example an optical resolution) without further purification; 1H NMR (CDCl3), δ =1.27 (m, 1H), 1.45 (m, 1H), 1.55 (m, 1H), 1.74 (m, 1H), 1.83 (m, 1H), 2.05 (m, 1H), 2.34 (s, 3H), 3.47 (m, 1H), 3.72 (m, 1H), 3.91 (s, 3H), 4.58 (dd, 2H), 7.15 (d, 1H), 7.20 (d, 2H), 7.27 (m, 1H). rose to 28° C The mixture was stirred for 30 min After washing three times with 3 l of n-heptane each time the remaining aqueous phase was extracted four times with 2.5 l of MTBE each time The combined MTBE phases were washed once with 5 l of water dried over Na2SO4 subsequently concentrated by evaporation under reduced pressure

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

Conditions: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 10.0 g (86 mmol) of cis-1,3-cyclohexanediol were taken up in 150 ml of methyl tert-butyl ether (MTBE), admixed at approx. 20° C. with 6.72 g (59.9 mmol) of potassium tert-butoxide (KOtBu) and stirred. After about 30 minutes, the suspension was cooled to 5° C. and admixed dropwise with 7.4 g (approx. 50%) of methyl 2-bromomethyl-6-methylbenzoate, which may be prepared, for example, by methanolyzing the acid bromide (2-bromomethyl-6-methylbenzoyl bromide) or by brominating methyl 2,6-dimethylbenzoate. The mixture was stirred at 0–5° C. for 1 h, heated to 20–23° C. and left to stir overnight. Water was added, the mixture was stirred vigorously, the phases were separated, the organic phase was washed once more with water and then the organic phase was concentrated under reduced pressure. The residue (4.6 g) was chromatographed on silica gel (1:1 ethyl acetate/n-heptane). 1.2 g of the desired compound were obtained as a light yellow oil, 1H NMR (CDCl3), δ =1.27 (m, 1H), 1.45 (m, 1H), 1.55 (m, 1H), 1.74 (m, 1H), 1.82 (m, 1H), 2.05 (m, 1H), 2.34 (s, 3H), 3.46 (m, 1H), 3.72 (m, 1H), 3.91 (s, 3H), 4.58 (dd, 2H), 7.15 (d, 1H), 7.20 (d, 2H), 7:27 (m, 1H). The mixture was stirred at 0–5° C. for 1 h heated to 20–23° C. left to stir overnight the mixture was stirred vigorously the phases were separated the organic phase was washed once more with water the organic phase was concentrated under reduced pressure The residue (4.6 g) was chromatographed on silica gel (1:1 ethyl acetate/n-heptane)

Conditions: temp:-5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 500 g (4.3 mol) of cis-1,3-cyclohexanediol were dissolved in 5 l of NMP and admixed with 336 g (3.0 mol) of potassium tert-butoxide (KOtBu). The internal temperature rose to 28° C. The mixture was stirred for 30 min, then cooled to −5° C. and admixed dropwise with 370 g (approx. 94%, approx. 1.4 mol) of methyl 2-bromomethyl-6-methylbenzoate which may be prepared, for example, by methanolyzing 2-bromomethyl-6-methylbenzoyl bromide or by brominating methyl 2,6-dimethylbenzoate. The mixture was stirred for 30 min and then diluted with 5 l of water. After washing three times with 3 l of n-heptane each time and discarding the n-heptane solutions, the remaining aqueous phase was extracted four times with 2.5 l of MTBE each time. The combined MTBE phases were washed once with 5 l of water, dried over Na2SO4 and subsequently concentrated by evaporation under reduced pressure. 234 g of the desired compound were obtained as a yellowish oil and were used in the next reaction (for example an optical resolution) without further purification; 1H NMR (CDCl3), δ =1.27 (m, 1H), 1.45 (m, 1H), 1.55 (m, 1H), 1.74 (m, 1H), 1.83 (m, 1H), 2.05 (m, 1H), 2.34 (s, 3H), 3.47 (m, 1H), 3.72 (m, 1H), 3.91 (s, 3H), 4.58 (dd, 2H), 7.15 (d, 1H), 7.20 (d, 2H), 7.27 (m, 1H). rose to 28° C The mixture was stirred for 30 min After washing three times with 3 l of n-heptane each time the remaining aqueous phase was extracted four times with 2.5 l of MTBE each time The combined MTBE phases were washed once with 5 l of water dried over Na2SO4 subsequently concentrated by evaporation under reduced pressure

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

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

Procedure: 24.2 g (221 mmol) of benzyl alcohol are added with ice cooling to 136 g (233 mmol) of 2-bromomethyl-6-methylbenzoyl bromide solution (35% solution in heptane). Subsequently, the mixture is left to stir at RT for one hour. After addition of 500 ml of tert-butyl methyl ether, the organic solution is washed successively with 410 ml of sat. sodium hydrogencarbonate solution and four times with 300 ml each time of water. Subsequently, the solvent is removed fully under reduced pressure. 74 g of benzyl 2-bromomethyl-6-methylbenzoate are obtained as a colorless oil having a purity of 80%. The benzyl 2-bromomethyl-6-methylbenzoate prepared in this way has a molecular weight of 318.02 (C16H15BrO2); MS (ESI): 341.0 [M+Na]+. Subsequently, the mixture is left the organic solution is washed successively with 410 ml of sat. sodium hydrogencarbonate solution and four times with 300 ml each time of water Subsequently, the solvent is removed fully under reduced pressure