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30th August 2013 @ 16:55

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Reaction information

*#Reaction file
ReactionScheme.cdx
 
*Reaction file type CDX
*Procedure

To a solution of ZrCp2Cl2 (321 mg, 1.1 mmol) in THF (5 mL) at –80 °C under Ar is added dropwise n-butyllithium (0.88 mL of a 2.5 M solution in hexanes, 2.2 mmol). In the case of substrates containing a free hydroxyl group, 2.2 equivalents of ZrCp2Cl2 (642 mg) and 4.4 equivalents of n-butyllithium (1.76 mL) are used. After the addition of butyllithium, a solution of the 5-(3-phenyl-4-pentenyl)-2,3-dihydrofuran (214 mg, 1 mmol) in THF (2 mL) is added dropwise and the solution allowed to warm to RT. After between 3 h and 16 h at RT, MeOH (3 mL) and saturated NaHCO3 solution (7 mL) are added and the cloudy white or pale yellow reaction mixture stirred for between 2 h and 16 h. After dilution of the reaction mixture with ether (20 mL) and water (20 mL), the aqueous phase is separated and extracted with ether (3 x 50 mL). The combined organic phases are combined and washed with brine, dried over MgSO­4, filtered and concentrated. The crude product was purified by column chromatography (SiO2, 20% ether in hexane) to provide the desired product as a viscous, clear colourless oil (150 mg, 69% yield). This product was obtained as a single diastereomer. 

*Yield (%) 69 
*Type of Yield Isolated Product Reaction 
Reference(s)

E. Negishi, F. E. Cederbaum, T. Takahashi, Tetrahedron Lett. 1986, 27, 2829.

DavidOwenThesis2000pp43,44,105.pdf
308LABBOOK.JPG
Further information Compound 308: (2S*,3R*)-3-(2-Methyl-3-phenylcyclopentyliden)-1-propanol

For multistep reactions (or their steps):

Overall reaction? True 
For overall reaction - links to child reaction steps N/A 
For step in multistep reaction - link to previous reaction step N/A 
For step in multistep reaction - link to following reaction step N/A 
Attached Files
30th August 2013 @ 16:49

This post is compatible for submission to ChemSpider Reactions.

See ChemSpider Reactions template - help and further information for help when using it.

Reaction information

*#Reaction file
ReactionScheme.cdx
 
*Reaction file type CDX
*Procedure

To a solution of ZrCp2Cl2 (321 mg, 1.1 mmol) in THF (5 mL) at –80 °C under Ar is added dropwise n-butyllithium (0.88 mL of a 2.5 M solution in hexanes, 2.2 mmol). In the case of substrates containing a free hydroxyl group, 2.2 equivalents of ZrCp2Cl2 (642 mg) and 4.4 equivalents of n-butyllithium (1.76 mL) are used. After the addition of butyllithium, a solution of the 2-(4-pentenyl)-4,5-dihydrofuran (331 mg, 2.4 mmol) in THF (2 mL) is added dropwise and the solution allowed to warm to RT. After between 3 h and 16 h at RT, MeOH (3 mL) and saturated NaHCO3 solution (7 mL) are added and the cloudy white or pale yellow reaction mixture stirred for between 2 h and 16 h. After dilution of the reaction mixture with ether (20 mL) and water (20 mL), the aqueous phase is separated and extracted with ether (3 x 50 mL). The combined organic phases are combined and washed with brine, dried over MgSO­4, filtered and concentrated. The crude oil was purified by column chromatography (SiO2, 25% ether in petrol) to give the desired product as a clear, colourless oil (263 mg, 78%).

*Yield (%) 78
*Type of Yield Isolated Product Yield 
Reference(s)

E. Negishi, F. E. Cederbaum, T. Takahashi, Tetrahedron Lett. 1986, 27, 2829.

DavidOwenThesis2000pp43,44,103,104.pdf
307LABBOOK.JPG
 
Further information Compound 307: 3-(2-(E)-Methylcyclopentyliden)-1-propanol 

For multistep reactions (or their steps):

Overall reaction? True 
For overall reaction - links to child reaction steps N/A 
For step in multistep reaction - link to previous reaction step N/A 
For step in multistep reaction - link to following reaction step N/A 
Attached Files
30th August 2013 @ 16:47

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Reaction information

*#Reaction file
reactionscheme_38f.cdx
*Reaction file type CDX
*Procedure

To a 30 mL Schlenk vial under argon at room temperature was added dppf (0.12 g, 0.21 mmol), sodium ethoxide (5 mL of a 2.0 M soln. in EtOH), 4-cyanobromobenzene (0.37 g, 2.0 mmol) and CyNC (0.38 mL, 3.0 mmol). PdCl2 (19.6 mg, 0.11 mmol) was then added against a counterflow of argon. Finally, dry toluene (14 mL) was used to wash all solids from the sides of the vial, which was then heated at 109 °C in a Stem block for 1.5 h. The reaction mixture was allowed to cool to room temperature before water (20 mL) was added. The organic layer was separated and the aqueous solution extracted with ether (4x15 mL). The combined organics were dried over MgSO4, filtered and evaporated. Work-up and purification on silica with petrol:ether (4:1 + 5% NEt3) gave the desired compound as a yellow oil, (0.37 g, 72%), consisting of a mixture of three isomers in a ratio of 90: 8.7 : 1.3. 

 

*Yield (%) 72 %
*Type of Yield Isolated pure product
Reference(s)
Gustaf Saluste p113-114.pdf
Further information  

For multistep reactions (or their steps):

Overall reaction? True
For overall reaction - links to child reaction steps  
For step in multistep reaction - link to previous reaction step  
For step in multistep reaction - link to following reaction step  
Attached Files
30th August 2013 @ 16:44

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Reaction information

*#Reaction file

ReactionScheme.cdx
*Reaction file type CDX
*Procedure

To a solution of 3,4-dihydro-2H-pyran (631 mg, 7.5 mmol) in THF (8 mL) at –40 °C under Ar, is added dropwise tert-butyllithium (6.1 mL of a 1.3 M solution in pentanes, 8 mmol). The solution is allowed to warm to 0 °C and stirred for 30 minutes before cooling to –20 °C and treatment with a solution of the 1-iodo-5-hexene (1.05 g, 5 mmol) in THF (2 mL). The yellow reaction mixture is allowed to warm to RT and heated at reflux for 1 h. The solution is allowed to cool and poured into saturated NaHCO3 solution (10 mL) and pentane (20 mL). The aqueous layer is separated and extracted with pentane (3 x 50 mL), and the combined organic phases dried over Na2SO4, filtered and concentrated. The crude product was purified by Kugelrohr distillation (100 °C, 0.8 mbar) to give the desired product as a clear, colourless oil (692 mg, 4.17 mmol, 83%). 

*Yield (%) 83
*Type of Yield Isolated Product Yield 
Reference(s)

P. J. Kocienski, M. Pritchard, S. N. Wadman, R. J. Whitby, C. L. Yeates, J. Chem. Soc. Perkin Trans. 1 1992, 24, 3419.

ReactionScheme.cdx
306LABBOOK.JPG
 
Further information Compound 306: 2-(5-Hexenyl)-5,6-dihydro-4H-pyran

For multistep reactions (or their steps):

Overall reaction? True
For overall reaction - links to child reaction steps N/A 
For step in multistep reaction - link to previous reaction step N/A 
For step in multistep reaction - link to following reaction step N/A 
Attached Files
30th August 2013 @ 16:43

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Reaction information

*#Reaction file
reactionscheme_38g.cdx
*Reaction file type CDX
*Procedure

To a 30 mL Schlenk vial under argon at room temperature was added dppf (0.11 g, 0.20 mmol), sodium phenoxide (6 mL of a 1.7 M soln. in THF), PhBr (0.37 g, 2.0 mmol) and CyNC (0.38 mL, 3.0 mmol). PdCl2 (20.0 mg, 0.11 mmol) was then added against a counterflow of argon. Finally, dry toluene (14mL) was used to wash all solids from the sides of the vial, which was then heated at 109 °C in a Stem block for 1.5 h. The reaction mixture was allowed to cool to room temperature before water (20 mL) was added. The organic layer was separated and the aqueous solution extracted with ether (4x15 mL). The combined organics were dried over MgSO4, filtered and evaporated. Work-up and purification on silica with petrol:ether (4:1 + 5% NEt3) gave the title compound as a dense, yellow oil, (0.50 g, 83%).

*Yield (%) 83 %
*Type of Yield Isolated pure product
Reference(s)
Gustaf Saluste p113.pdf
Further information  

For multistep reactions (or their steps):

Overall reaction? True
For overall reaction - links to child reaction steps  
For step in multistep reaction - link to previous reaction step  
For step in multistep reaction - link to following reaction step  
Attached Files