9-azido-9H-fluorene

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: 9-Bromo-9H-fluorene (1.00 g, 4.08 mmol) was dissolved in acetone (7 mL). To this was added a solution of NaN3 (1.33 g, 20.4 mmol) in H2O (3 mL). The resulting solution was stirred overnight. Acetone was removed by concentration under reduced pressure. The resulting aqueous mixture was extracted with CH2Cl2 (2×15 mL), and the organic layers were combined, dried over Na2SO4(s), filtered, and concentrated under reduced pressure. The resulting solid residue was purified by silica gel flash chromatography, eluting with hexanes, to give azide 2j as a white solid (0.74 g, 3.57 mmol, 87% yield). Acetone was removed by concentration under reduced pressure The resulting aqueous mixture was extracted with CH2Cl2 (2×15 mL) dried over Na2SO4(s) filtered concentrated under reduced pressure The resulting solid residue was purified by silica gel flash chromatography eluting with hexanes

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

Procedure: To probe the scope of the reaction even further, we investigated the synthesis of semi-stabilized diazo-compounds. Treatment of 9-azido-fluorene 2j with phosphine 1e under anhydrous conditions at low temperature (toluene, 0° C.), followed by loading the red solution directly on basic alumina (Grade 5) and eluting with 10% CH2Cl2/hexanes, 9-diazo-fluorene 5j was isolated in 85% yield and excellent purity (96%). Apparently, thermal fragmentation of the putative triazenophosphonium salt, which more than likely exists in its neutral λ5-phosphorane form[16] is suppressed sufficiently for this substrate under the reaction conditions. The low temperature and low polarity of the solvent probably contribute to that greater stability. Under the standard conditions (THF/H2O), incomplete conversion of the azide 2j and contamination of the diazo-compound 5j with substantial amounts of other products, probably arising from alternative triazene decomposition and dimerization of the diazo-compound, were apparent. Finally, a vinylogous diazo-carbonyl compound 5k (96% purity) was prepared in good yield from anthraquinone-based azide 2k using the standard conditions. is suppressed sufficiently for this substrate under the reaction conditions

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

Procedure: To probe the scope of the reaction even further, we investigated the synthesis of semi-stabilized diazo-compounds. Treatment of 9-azido-fluorene 2j with phosphine 1e under anhydrous conditions at low temperature (toluene, 0° C.), followed by loading the red solution directly on basic alumina (Grade 5) and eluting with 10% CH2Cl2/hexanes, 9-diazo-fluorene 5j was isolated in 85% yield and excellent purity (96%). Apparently, thermal fragmentation of the putative triazenophosphonium salt, which more than likely exists in its neutral λ5-phosphorane form[16] is suppressed sufficiently for this substrate under the reaction conditions. The low temperature and low polarity of the solvent probably contribute to that greater stability. Under the standard conditions (THF/H2O), incomplete conversion of the azide 2j and contamination of the diazo-compound 5j with substantial amounts of other products, probably arising from alternative triazene decomposition and dimerization of the diazo-compound, were apparent. Finally, a vinylogous diazo-carbonyl compound 5k (96% purity) was prepared in good yield from anthraquinone-based azide 2k using the standard conditions. the scope of the reaction even further the synthesis of semi-stabilized diazo-compounds eluting with 10% CH2Cl2/hexanes

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

Procedure: To probe the scope of the reaction even further, we investigated the synthesis of semi-stabilized diazo-compounds. Treatment of 9-azido-fluorene 2j with phosphine 1e under anhydrous conditions at low temperature (toluene, 0° C.), followed by loading the red solution directly on basic alumina (Grade 5) and eluting with 10% CH2Cl2/hexanes, 9-diazo-fluorene 5j was isolated in 85% yield and excellent purity (96%). Apparently, thermal fragmentation of the putative triazenophosphonium salt, which more than likely exists in its neutral λ5-phosphorane form[16] is suppressed sufficiently for this substrate under the reaction conditions. The low temperature and low polarity of the solvent probably contribute to that greater stability. Under the standard conditions (THF/H2O), incomplete conversion of the azide 2j and contamination of the diazo-compound 5j with substantial amounts of other products, probably arising from alternative triazene decomposition and dimerization of the diazo-compound, were apparent. Finally, a vinylogous diazo-carbonyl compound 5k (96% purity) was prepared in good yield from anthraquinone-based azide 2k using the standard conditions. the scope of the reaction even further the synthesis of semi-stabilized diazo-compounds eluting with 10% CH2Cl2/hexanes

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

Procedure: 9-Bromo-9H-fluorene (1.00 g, 4.08 mmol) was dissolved in acetone (7 mL). To this was added a solution of NaN3 (1.33 g, 20.4 mmol) in H2O (3 mL). The resulting solution was stirred overnight. Acetone was removed by concentration under reduced pressure. The resulting aqueous mixture was extracted with CH2Cl2 (2×15 mL), and the organic layers were combined, dried over Na2SO4(s), filtered, and concentrated under reduced pressure. The resulting solid residue was purified by silica gel flash chromatography, eluting with hexanes, to give azide 2j as a white solid (0.74 g, 3.57 mmol, 87% yield). Acetone was removed by concentration under reduced pressure The resulting aqueous mixture was extracted with CH2Cl2 (2×15 mL) dried over Na2SO4(s) filtered concentrated under reduced pressure The resulting solid residue was purified by silica gel flash chromatography eluting with hexanes

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

Procedure: To probe the scope of the reaction even further, we investigated the synthesis of semi-stabilized diazo-compounds. Treatment of 9-azido-fluorene 2j with phosphine 1e under anhydrous conditions at low temperature (toluene, 0° C.), followed by loading the red solution directly on basic alumina (Grade 5) and eluting with 10% CH2Cl2/hexanes, 9-diazo-fluorene 5j was isolated in 85% yield and excellent purity (96%). Apparently, thermal fragmentation of the putative triazenophosphonium salt, which more than likely exists in its neutral λ5-phosphorane form[16] is suppressed sufficiently for this substrate under the reaction conditions. The low temperature and low polarity of the solvent probably contribute to that greater stability. Under the standard conditions (THF/H2O), incomplete conversion of the azide 2j and contamination of the diazo-compound 5j with substantial amounts of other products, probably arising from alternative triazene decomposition and dimerization of the diazo-compound, were apparent. Finally, a vinylogous diazo-carbonyl compound 5k (96% purity) was prepared in good yield from anthraquinone-based azide 2k using the standard conditions. is suppressed sufficiently for this substrate under the reaction conditions

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

Procedure: To probe the scope of the reaction even further, we investigated the synthesis of semi-stabilized diazo-compounds. Treatment of 9-azido-fluorene 2j with phosphine 1e under anhydrous conditions at low temperature (toluene, 0° C.), followed by loading the red solution directly on basic alumina (Grade 5) and eluting with 10% CH2Cl2/hexanes, 9-diazo-fluorene 5j was isolated in 85% yield and excellent purity (96%). Apparently, thermal fragmentation of the putative triazenophosphonium salt, which more than likely exists in its neutral λ5-phosphorane form[16] is suppressed sufficiently for this substrate under the reaction conditions. The low temperature and low polarity of the solvent probably contribute to that greater stability. Under the standard conditions (THF/H2O), incomplete conversion of the azide 2j and contamination of the diazo-compound 5j with substantial amounts of other products, probably arising from alternative triazene decomposition and dimerization of the diazo-compound, were apparent. Finally, a vinylogous diazo-carbonyl compound 5k (96% purity) was prepared in good yield from anthraquinone-based azide 2k using the standard conditions. the scope of the reaction even further the synthesis of semi-stabilized diazo-compounds eluting with 10% CH2Cl2/hexanes

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

Procedure: 9-Bromo-9H-fluorene (1.00 g, 4.08 mmol) was dissolved in acetone (7 mL). To this was added a solution of NaN3 (1.33 g, 20.4 mmol) in H2O (3 mL). The resulting solution was stirred overnight. Acetone was removed by concentration under reduced pressure. The resulting aqueous mixture was extracted with CH2Cl2 (2×15 mL), and the organic layers were combined, dried over Na2SO4(s), filtered, and concentrated under reduced pressure. The resulting solid residue was purified by silica gel flash chromatography, eluting with hexanes, to give azide 2j as a white solid (0.74 g, 3.57 mmol, 87% yield). Acetone was removed by concentration under reduced pressure The resulting aqueous mixture was extracted with CH2Cl2 (2×15 mL) dried over Na2SO4(s) filtered concentrated under reduced pressure The resulting solid residue was purified by silica gel flash chromatography eluting with hexanes

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

Procedure: To probe the scope of the reaction even further, we investigated the synthesis of semi-stabilized diazo-compounds. Treatment of 9-azido-fluorene 2j with phosphine 1e under anhydrous conditions at low temperature (toluene, 0° C.), followed by loading the red solution directly on basic alumina (Grade 5) and eluting with 10% CH2Cl2/hexanes, 9-diazo-fluorene 5j was isolated in 85% yield and excellent purity (96%). Apparently, thermal fragmentation of the putative triazenophosphonium salt, which more than likely exists in its neutral λ5-phosphorane form[16] is suppressed sufficiently for this substrate under the reaction conditions. The low temperature and low polarity of the solvent probably contribute to that greater stability. Under the standard conditions (THF/H2O), incomplete conversion of the azide 2j and contamination of the diazo-compound 5j with substantial amounts of other products, probably arising from alternative triazene decomposition and dimerization of the diazo-compound, were apparent. Finally, a vinylogous diazo-carbonyl compound 5k (96% purity) was prepared in good yield from anthraquinone-based azide 2k using the standard conditions. is suppressed sufficiently for this substrate under the reaction conditions

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

Procedure: To probe the scope of the reaction even further, we investigated the synthesis of semi-stabilized diazo-compounds. Treatment of 9-azido-fluorene 2j with phosphine 1e under anhydrous conditions at low temperature (toluene, 0° C.), followed by loading the red solution directly on basic alumina (Grade 5) and eluting with 10% CH2Cl2/hexanes, 9-diazo-fluorene 5j was isolated in 85% yield and excellent purity (96%). Apparently, thermal fragmentation of the putative triazenophosphonium salt, which more than likely exists in its neutral λ5-phosphorane form[16] is suppressed sufficiently for this substrate under the reaction conditions. The low temperature and low polarity of the solvent probably contribute to that greater stability. Under the standard conditions (THF/H2O), incomplete conversion of the azide 2j and contamination of the diazo-compound 5j with substantial amounts of other products, probably arising from alternative triazene decomposition and dimerization of the diazo-compound, were apparent. Finally, a vinylogous diazo-carbonyl compound 5k (96% purity) was prepared in good yield from anthraquinone-based azide 2k using the standard conditions. the scope of the reaction even further the synthesis of semi-stabilized diazo-compounds eluting with 10% CH2Cl2/hexanes