4-BROMO-6,7-DIMETHOXYQUINOLINE

yellow powder

Weigh the compound having the structure shown in Formula XVIII (1.5 g, 6.7 mmol) into a suffocating can, Then add 15 mL of acetic acid and 15 mL of 40percent hydrobromic acid, Warm to 140°C overnight (about 15 hours). No raw material was detected by LC-MS while part of 6, 7-dimethyloxy-4-bromoquinoline was generated.After the reaction solution was directly evaporated, 25 mL of water was added for pulping.Then use a small amount of ammonia to adjust the pH to about 10 and beat it for 1 hour.The solid was collected by suction filtration, and the mixture was azeotropically boiled with absolute ethanol (20 mL) three times.Then pump to constant weight. 1.3 g of a white solid is obtained. FIG. 1 shows the spectrum. Upon analysis, the white solid contained two substances, 6, 7-dimethyloxy-4-chloroquinoline (formula XII-1) and 6, 7-dimethyloxy-4-bromoquinoline (formula XII-2), based on H-NMR results, see Figure 2, we can see thatThe ratio of the amount of the two substances is approximately 1:1.7. Yield 86.3percent.General procedure: To a solution of AB-region starting material (1.0 equiv) in THF was added dropwise 2.5 M n-BuLi solution in n-hexane (1.05 equiv) at -78 °C. The reaction mixture was stirred for 10 min at -78 °C, and DE-region aldehyde (1.0 equiv) was added. The reaction mixture was stirred for an additional 30 min and was warmed to ambient temperature. The reaction mixture was quenched with saturated NH4Cl solution and extracted with EtOAc. The organic layer was washed with brine, dried over MgSO4, and concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel to afford the corresponding compound.General procedure: To a solution of AB-region starting material (1.0 equiv) in THF was added dropwise 2.5 M n-BuLi solution in n-hexane (1.05 equiv) at -78 °C. The reaction mixture was stirred for 10 min at -78 °C, and DE-region aldehyde (1.0 equiv) was added. The reaction mixture was stirred for an additional 30 min and was warmed to ambient temperature. The reaction mixture was quenched with saturated NH4Cl solution and extracted with EtOAc. The organic layer was washed with brine, dried over MgSO4, and concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel to afford the corresponding compound.General procedure: To a solution of AB-region starting material (1.0 equiv) in THF was added dropwise 2.5 M n-BuLi solution in n-hexane (1.05 equiv) at -78 °C. The reaction mixture was stirred for 10 min at -78 °C, and DE-region aldehyde (1.0 equiv) was added. The reaction mixture was stirred for an additional 30 min and was warmed to ambient temperature. The reaction mixture was quenched with saturated NH4Cl solution and extracted with EtOAc. The organic layer was washed with brine, dried over MgSO4, and concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel to afford the corresponding compound.General procedure: To a solution of AB-region starting material (1.0 equiv) in THF was added dropwise 2.5 M n-BuLi solution in n-hexane (1.05 equiv) at -78 °C. The reaction mixture was stirred for 10 min at -78 °C, and DE-region aldehyde (1.0 equiv) was added. The reaction mixture was stirred for an additional 30 min and was warmed to ambient temperature. The reaction mixture was quenched with saturated NH4Cl solution and extracted with EtOAc. The organic layer was washed with brine, dried over MgSO4, and concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel to afford the corresponding compound.

Molecular Weight:268.11
XLogP3:2.8
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:2
Exact Mass:266.98949
Monoisotopic Mass:266.98949
Topological Polar Surface Area:31.4
Heavy Atom Count:15
Complexity:215
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes