3-Hexylthiophene

colorless transparent or light yellow liquid

Starting from the commercially available products 3-bromothiophene (3-BT) and hexylmagnesiumbromide, 1 was produced using a Ni catalyst. In a three-necked flask, 100ml (1 eq, 166.0 g, 1.018 mol) of bromothiophene is stirred under nitrogen atmosphere with 0.01 equivalent of Ni(dppp)CIStarting from the commercially available products 3-bromothiophene (3- BT) and hexylmagnesiumbromide, 1 was produced using a Ni catalyst. In a three-necked flask, 100ml (1 eq, 166.0 g, 1 .018 mol) of bromothiophene is stirred under nitrogen atmosphere with 0.01 equivalent of Ni(dppp)Cl2 (5.19 g, 0.0102 mol) and 300ml dry diethylether. 1 .2 equivalent (0.61 1 I of a 2.0M solution in diethyl ether, 1 .22 mol) of hexylmagnesiumbromide was added dropwise at a temperature of 0°C. The reaction was stirred overnight at room temperature before neutralisation by addition of a 1 M HCI solution. After extraction with diethyl ether, washing with a saturated NaHCO3-Hexylthiophene was prepared similarly to a method described by Ng et al.9 and was modifiedas follows: magnesium (2.55 g, 105 mmol) was stirred without solvent under nitrogen for 1 h inorder to activate the surface. A solution of 1-bromohexane (14.9 g, 90.0 mmol) in dry diethyl ether (75 mL) was added dropwise to a suspension of the activated magnesium in diethyl ether(45 mL) within 1 h at 20 °C. The reaction mixture was heated to reflux for another 1 h. The resulting Grignard reagent was added to 3-bromothiophene (12.23 g, 75.00 mmol) and [Ni(dppp)Cl2] (81 mg, 15 mmol, 0.2 molpercent) in diethyl ether(45 mL) at 0 °C via syringe over the course of 30 min and the mixture was stirred for 4 h at 20 °C. The reaction mixture was quenched with aqueous hydrochloric acid (1 M, 60 mL) at 0 °C. Then the aqueous layer was extracted with diethyl ether (4 x 50 mL). The combined organic layers were dried over MgSO4 and the volatiles were removed in vacuo. The residue was purified by vigreux distillation (110 °C, 6 mbar) to yield 10.2 g (81percent, lit.9 71percent) of colorless oil.After stirring a mixture of magnesium turnings (10.3 g, 421.2 mmol) and 1-bromohexane (59.3 mL, 422.2 mmol) in 80 mL of anhydrous THF for 2 h at 70 °C under argon atmosphere, the mixture was treated with a solution of 3-bromothiophene (20 mL, 211.1 mmol) and Ni(dppp)ClAdded to a flask are 57.1 g (2.35 mol) of magnesium metal and 700 ml of 2-methyl-tetrahydrofuran. The flask contents are heated to 60-70° C. A reaction is initiated by adding 5 ml of hexylmagnesiumbromide (1 N) in 2-methyl-tetrahydrofuran to the flask. The Grignard reagent concentration in the solvent is 3.35 mol/L. The flask temperature is increased to 80-85° C. Next, 396 g of bromohexane (2.4 mol) is added to the flask over a period of 2.5 hours. The flask is then heated to reflux and stirred for an additional two hours. After two hours, the flask is cooled down to 15-20° C. Thereafter, add a suspension of 1.6 g of Ni(dppp)ClEXAMPLE 6 (COMPARATIVE); A hexylmagnesiumbromide Grignard reagent (1 eq.) was added to a mixture of a 100percent tetrahydrofuran solvent, 3-bromothiophene (1 eq.) and with 200 mg of a dichloro-bis(triphenylphosphine) nickel (II) catalyst. The Grignard reagent concentration in the solvent is 1 mol/L. The reaction was conducted at 60° C. Immediate gas chromatography of the reaction product showed 9.6percent 3-bromothiophene, 36.2percent 3-hexylthiophene and 25.7percent bis-thienyl side-product. GC after one hour showed 6.6percent3-bromothiophene, 38.6percent 3-hexylthiophene and 27.1percent bis-thienyl side-product. GC after 2.5 hours showed 3.3percent 3-bromothiophene, 37.7percent 3-hexylthiophene and 20.3percent bis-thienyl side-product. The high temperature (60° C.) and 100percent tetrahydrofuran solvent gave low selectivity, incomplete conversion, and an undesirable amount of bis-thienyl side product; EXAMPLE 7 (COMPARATIVE); A hexylmagnesiumbromide Grignard reagent (1 eq.) was added to a mixture of a 100percent tetrahydrofuran solvent, 3-bromothiophene (1 eq.) and with 200 mg of a dichloro-bis(triphenylphosphine) nickel (II) catalyst. The Grignard reagent concentration in the solvent is 1 mol/L. The reaction was conducted at 0° C. Immediate gas chromatography of the reaction product showed 0.09percent 3-bromothiophene, 82.7percent 3-hexylthiophene and 6.6percent bis-thienyl side-product. GC after one hour showed 0.09percent 3-bromothiophene, 82.3percent 3-hexylthiophene and 6.7percent bis-thienyl side-product. GC after 2.5 hours showed 0.5percent 3-bromothiophene, 81.5percent 3-hexylthiophene and 6.4percent bis-thienyl side-product. The low temperature (0° C.) gave satisfactory selectivity but an undesirable amount of bis-thienyl side product.EXAMPLE 10 (COMPARATIVE); 3-Bromothiophene (1 eq.) is reacted with a hexylmagnesiumbromide Grignard reagent (1.2 eq.) in a 100percent diethylether solvent and with 200 mg of a dichloro-bis(triphenylphosphine) palladium(II) catalyst. The Grignard reagent concentration in the solvent is 2 mol/L. The reaction was conducted at room temperature. Immediate gas chromatography of the reaction product showed 77.2percent 3-bromothiophene, 4.2percent 3-hexylthiophene and 0.5percent bis-thienyl side-product. GC after one hour showed 78.1percent 3-bromothiophene, 4.0percent 3-hexylthiophene and 0.2percent bis-thienyl side-product. GC after 2.5 hours showed 76.8percent 3-bromothiophene, 4.5percent 3-hexylthiophene and 0.3percent bis-thienyl side-product. The diethylether solvent and dichloro-bis(triphenylphosphino) palladium(II) catalyst gave a bad conversion percentage.(COMPARATIVE); 3-Bromothiophene (1 eq.) is reacted with a hexylmagnesiumbromide Grignard reagent (1.2 eq.) in a 100percent diethylether solvent and with 12.6 mg of a dichloro-bis(triphenylphosphine) nickel (II) catalyst. The Grignard reagent concentration in the solvent is 2 mol/L. The reaction was conducted at room temperature. Immediate gas chromatography of the reaction product showed 85.3percent 3-bromothiophene, 1.7percent 3-hexylthiophene and 0.5percent bis-thienyl side-product. GC after one hour showed 68.0percent 3-bromothiophene, 3.1percent 3-hexylthiophene, 6.3percent bis-thienyl side-product and 0.89percent. This shows bad conversion with a diethylether solvent and a dichloro-bis(triphenylphosphine) nickel (II) catalyst.3-Bromothiophene (1 eq.) is reacted with a hexylmagnesiumbromide Grignard reagent (1.2 eq.) in a 100percent diethylether solvent and with no catalyst. The Grignard reagent concentration in the solvent is 2 mol/L. The reaction was conducted at room temperature. Immediate gas chromatography of the reaction product showed 85.7percent 3-bromothiophene, 0.5percent 3-hexylthiophene and 0.4percent bis-thienyl side-product. GC after one hour showed 85.7percent 3-bromothiophene, 1.1percent 3-hexylthiophene and 0.2percent bis-thienyl side-product. This shows almost no conversion with no catalyst.A hexylmagnesiumbromide Grignard reagent (1 eq.) was added to mixture of a 50:50 tetrahydrofuran/toluene solvent, 3-bromothiophene (1 eq.) and 200 mg of a dichloro-bis(triphenylphosphine) palladium(II) catalyst. The Grignard reagent concentration in the solvent is 1 mol/L. The reaction was conducted at 80° C. Immediate gas chromatography (GC) of the reaction product showed 15.2percent 3-bromothiophene, 38.0percent 3-hexylthiophene and 17.9percent bis-thienyl side-product. GC after one hour showed 2.0percent 3-bromothiophene, 40.7percent 3-hexylthiophene and 23.9percent bis-thienyl side-product. GC after 2.5 hours showed 1.3percent 3-bromothiophene, 42.1percent 3-hexylthiophene, 24.3percent bis-thienyl side-product and 2.53percent 3-(1-methylpentyl)thiophene. This results show a low selectivity using a dichloro-bis(triphenylphosphine) palladium(II) catalyst and 50:50 THF/toluene solvent. Also an undesirable amount of bis-thienyl and 3-(1-methylpentyl)thiophene side products.3-Bromothiophene (1 eq.) is reacted with a hexylmagnesiumbromide Grignard reagent (1.2 eq.) in a 100percent diethylether solvent and with 200 mg of a Nickel (II) acetylacetonate catalyst. The Grignard reagent concentration in the solvent is 2 mol/L. The reaction was conducted at room temperature. Immediate gas chromatography of the reaction product showed 60.0percent 3-bromothiophene, 5.7percent 3-hexylthiophene and 5.9percent bis-thienyl side-product. GC after one hour showed 40.1percent 3-bromothiophene, 12.7percent 3-hexylthiophene, 16.2percent bis-thienyl side-product and 2.4percent 3-(1-methylpentyl)thiophene. The nickel (II) acetylacetonate catalyst and diethylether solvent gave incomplete conversion.(COMPARATIVE); 3-Bromothiophene (1 eq.) is reacted with a hexylmagnesiumbromide Grignard reagent (1.2 eq.) in a 100percent diethylether solvent and with 200 mg of a dichloro-bis(triphenylphosphine) palladium(II) catalyst. The Grignard reagent concentration in the solvent is 2 mol/L. The reaction was conducted at 0° C. Immediate gas chromatography of the reaction product showed 0.09percent 3-bromothiophene, 81.5percent 3-hexylthiophene and 5.3percent bis-thienyl side-product. GC after one hour showed 0.09percent 3-bromothiophene, 82.5percent 3-hexylthiophene and 5.1percent bis-thienyl side-product. GC after 2.5 hours showed 0.07percent 3-bromothiophene, 82.9percent 3-hexylthiophene, 5.2percent bis-thienyl side-product and 0.09percent3-(1-methylpentyl)thiophene. The diethylether solvent, 0° C. reaction temperature and dichloro-bis(triphenylphosphine) palladium(II) catalyst gave complete conversion and good selectivity (80percent), but 5.2percent bis-thienyl side-product.A hexylmagnesiumbromide Grignard reagent (1 eq.) was added to a mixture of a 50:50 THF/toluene solvent, 3-bromothiophene (1 eq.) and 200 mg of a dichloro-bis(triphenylphosphine) nickel (II) catalyst. The Grignard reagent concentration in the solvent is 1 mol/L. The reaction was conducted at room temperature. Immediate gas chromatography of the reaction product showed 7.1percent 3-bromothiophene, 66.8percent 3-hexylthiophene and 12.6percent bis-thienyl side-product. GC after one hour showed 2.2percent 3-bromothiophene, 70.4percent 3-hexylthiophene and 13.3percent bis-thienyl side-product. GC after 2.5 hours showed 2.1percent 3-bromothiophene, 68.8percent 3-hexylthiophene, 14.0percent bis-thienyl side-product and 0.23percent 3-(1-methylpentyl)thiophene. The results show better selectivity using a dichloro-bis(triphenylphosphine) nickel (II) catalyst and 50:50 THF/toluene solvent than in Example 5, but incomplete conversion and an undesirable amount of bis-thienyl side product.EXAMPLE 8 (COMPARATIVE) ; 3-Bromothiophene (1 eq.) is reacted with a hexylmagnesiumbromide Grignard reagent (1.2 eq.) in a 100percent diethylether solvent and with 200 mg of a dichloro-bis(triphenylphosphine) nickel (II) catalyst. The Grignard reagent concentration in the solvent is 2 mol/L. The reaction was conducted at room temperature. Immediate gas chromatography of the reaction product showed 0.2percent 3-bromothiophene, 74.3percent 3-hexylthiophene and 10.5percent bis-thienyl side-product. GC after one hour showed 0.1percent 3-bromothiophene, 73.6percent 3-hexylthiophene and 11.85percent bis-thienyl side-product. GC after 2.5 hours showed 0.3percent 3-bromothiophene, 73.3percent 3-hexylthiophene, 10.7percent bis-thienyl side-product and 0.09percent 3-(1-methylpentyl)thiophene. The diethylether solvent gave complete conversion but selectivity was only 70percent and an undesirable amount of bis-thienyl side product was formed.(COMPARATIVE); 3-Bromothiophene (1 eq.) is reacted with a hexylmagnesiumbromide Grignard reagent (1.2 eq.) in a 100percent diethylether solvent and with 200 mg of a (1, 3-bis (diphenylphosphino)propane)dichloro Nickel (II) catalyst. The Grignard reagent concentration in the solvent is 2 mol/L. The reaction was conducted at room temperature. Immediate gas chromatography of the reaction product showed 0.1percent 3-bromothiophene, 91.2percent 3-hexylthiophene and 0.13percent bis-thienyl side-product. GC after one hour showed 0.2percent 3-bromothiophene, 90.0percent 3-hexylthiophene and 0.2percent bis-thienyl side-product. GC after 2.5 hours showed 0.16percent 3-bromothiophene, 90.7percent 3-hexylthiophene, 0.2percent bis-thienyl side-product and 0.4percent 3-(1-methylpentyl)thiophene. The diethylether solvent and (1, 3-bis (diphenylphosphino)propane)dichloro Nickel (II) catalyst gave a selectivity of 90percent. This reaction mixture undesirably forms a solid at the 2 mol/L concentration and therefore cannot be worked up in a plant scale due to the inability of the solid to be purged on water, which then requires the addition of water to the reaction. This may lead to accumulation of water which can suddenly react, leading to uncontrolled development of heat, and presenting serious safety concerns; (COMPARATIVE); 3-Bromothiophene (1 eq.) is reacted with a hexylmagnesiumbromide Grignard reagent (1.2 eq.) in a 100percent diethylether solvent and with 12.6 mg of a (1, 3-bis (diphenylphosphino)propane)dichloro Nickel (II) catalyst. The Grignard reagent concentration in the solvent is 2 mol/L. The reaction was conducted at room temperature. Immediate gas chromatography of the reaction product showed 60.9percent 3-bromothiophene, 27.2percent 3-hexylthiophene and 0.3percent bis-thienyl side-product. GC after one hour showed 45.6percent 3-bromothiophene, 42.9percent 3-hexylthiophene and 0.3percent bis-thienyl side-product. GC after 2.5 hours showed 35.6percent 3-bromothiophene, 51.8percent 3-hexylthiophene, 0.3percent bis-thienyl side-product and 0.31percent 3-(1-methylpentyl)thiophene. A reduced amount of (1, 3-bis (diphenylphosphino)propane)dichloro Nickel (II) catalyst and diethylether solvent gave incomplete conversion.

Conductive polymer precursor

Molecular Weight:168.30
XLogP3:5
Hydrogen Bond Acceptor Count:1
Rotatable Bond Count:5
Exact Mass:168.09727168
Monoisotopic Mass:168.09727168
Topological Polar Surface Area:28.2
Heavy Atom Count:11
Complexity:90.9
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes