1-bromo-4-diethoxyphosphorylbutane

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

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

Procedure: In another method, 1,4-dibromobutane is heated with triethylphosphite to give diethyl-4-bromobutylphosphonate, for example, as described by Eberhard and Westheimer, 1965. The resultant bromide is then reacted with, for example, biphenyl-4-carboxylic acid in dimethylformamide, in the presence of potassium carbonate. Again, the phosphate ester groups, e.g., ethyl groups, are removed e.g., with trimethylsilylbromide or left in place. An example of such a method is illustrated in the following scheme.

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

Procedure: In another method, 1,4-dibromobutane is heated with triethylphosphite to give diethyl-4-bromobutylphosphonate, for example, as described by Eberhard and Westheimer, 1965. The resultant bromide is then reacted with, for example, biphenyl-4-carboxylic acid in dimethylformamide, in the presence of potassium carbonate. Again, the phosphate ester groups, e.g., ethyl groups, are removed e.g., with trimethylsilylbromide or left in place. An example of such a method is illustrated in the following scheme.

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

Procedure: 1.34 g of KOH in ethanol were added dropwise to a mixture of 2,6-dihydroxynaphthalene (1.6g, 10 mmol) and diethyl(4-bromobutyl)phosphonate (6.0 g, 22 mmol) in ethanol, the mixture was left at room temperature for over night. The product was extracted with CH2Cl2. The CH2Cl2 solution was dried, leaving a brownish solid. The ester was purified by column chromatography. The bisphosphonate ester was converted to the acid by overnight stirring with 4-fold excess of bromotrimethylsilane in dry dichloromethane followed by addition of water. The bisphosphonic acid derivative was washed with CH2Cl2, filtered and collected. the mixture was left at room temperature for over night The product was extracted with CH2Cl2 The CH2Cl2 solution was dried leaving a brownish solid The ester was purified by column chromatography followed by addition of water The bisphosphonic acid derivative was washed with CH2Cl2 filtered collected

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

Procedure: 2,6-dihydroxyanthraquinone (1.19 g, 4.98 mmol) and diethyl(4-bromobutyl)phosphonate (3.0 g, 10 mmol) were heated at 60 ° C. in 5 ml DMF in the presence of 0.8 g of K2CO3 for 72 hours. The solution was extracted with CH2Cl2. The CH2Cl2 solution was dried, leaving a yellow solid. The ester was purified by column chromatography. The bisphosphonate ester was converted to the acid by overnight stirring with 4-fold excess of bromotrimethylsilane in dry dichloromethane followed by addition of water. The bisphosphonic acid derivative was washed with CH2Cl2, filtered and collected. The solution was extracted with CH2Cl2 The CH2Cl2 solution was dried leaving a yellow solid The ester was purified by column chromatography followed by addition of water The bisphosphonic acid derivative was washed with CH2Cl2 filtered collected

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

Procedure: In another method, 1,4-dibromobutane is heated with triethylphosphite to give diethyl-4-bromobutylphosphonate, for example, as described by Eberhard and Westheimer, 1965. The resultant bromide is then reacted with, for example, biphenyl-4-carboxylic acid in dimethylformamide, in the presence of potassium carbonate. Again, the phosphate ester groups, e.g., ethyl groups, are removed e.g., with trimethylsilylbromide or left in place. An example of such a method is illustrated in the following scheme.