4 4'-DI-TERT-BUTYL-2 2'-DIPYRIDYL98

white cyrstalline powder

In this example, following Example 1, the synthesis of 4, 4′-di-tert-butyl-2, 2′-bipyridine was investigated. In this example, the synthesis was performed through the reaction of 4-tert-butylpyridine with SD at low concentrations in THF. 4-tert-Butylpyridine (0.5 mmol) was reacted with SD in an amount of molar equivalents with respect to 4-tert-butylpyridine as shown in FIG. 2 in THF. The usage amounts of THF, the reaction temperatures and the reaction times were set as shown in FIG. 2, and the synthesis was performed in the same manner as in Example 1. After the reaction, in the same manner as in Example 1, the production amounts of 4, 4′-di-tert-butyl2, 2′-bipyridine (Compound 2), which was the target reaction product, and 4-tert-butyl-1, 4-dihydropyridine (Compound 1) and 4, 4′, 4″-tri-tert-butyl-2, 2′:6′, 2″-terpyridine (Compound 3), which were the possible reaction by-products, were measured, and their yields were calculated. The recovery rate of the unreacted 4-tert-butylpyridine was calculated in the same manner. The results are summarized in FIG. 2. It is found from these results that when 4-tert-butylpyridine (0.5 mmol) was reacted with SD in an amount of 1 to 2 mol equivalents with respect to the 4-tert-butylpyridine in 2 to 4 ml of THF at 25 to 50° C. for 1 to 24 hours, the 4, 4′-di-tert-butyl-2, 2′-bipyridine compound was obtained with a high yield in all of the cases. In particular, when 0.5 mmol 4-tert-butylpyridine was reacted with SD in an amount of 1 mol equivalent with respect to the 4-tert-butylpyridine in 2 ml of THF at 50° C. for 1 to 6 hours, the 4, 4′-di-tert-butyl-2, 2′-bipyridine compound was obtained with a high yield without the generation of reaction by-products. In addition, when 0.5 mmol 4-tert-butylpyridine was reacted with SD in an amount of 1 mol equivalent with respect to the 4-tert-butylpyridine in 4 ml of THF at 25° C. for 6 hours, the 4, 4′-di-tert-butyl-2, 2′-bipyridine compound was obtained with a high yield without the generation of reaction by-products. It was found that when SD in an amount of 2 mol equivalents was used, the yield decreased compared with the case of 1 mol equivalent, and the material balance also decreased. It was also found from comparison with that the lower the concentrations of 4-tert-butylpyridine and SD were with respect to THF, the higher the yield was.General procedure: On the benchtop, a 50 mL round-bottomed flask equipped with a inch Teflon coated magnetic stir bar was charged with NiBr2·3H2O(401 mg, 1.47 mmol) and DMF (20.0 mL). The vessel was stopperedwith a rubber septum and heated to 60 °C until a green homogeneoussolution resulted (approx. 20 min). Once homogeneity wasachieved, the vessel was removed from the heat and allowed to coolto r.t. Once at r.t., 4-tert-butyl-2-chloropyridine (2a; 4.99 g, 29.4mmol) and Mn powder (–325 mesh, 3.30 g, 60.0 mmol) were added, and the vessel was resealed with the septum, purged with argon, andheated again to 60 °C for the duration of the reaction. Reactionprogress was monitored by GC analysis of aliquots of the crude reactionmixture. In general, the reaction turns very dark brown orblack in color when complete, and the color change is a reliable indicatorfor the reaction endpoint. Upon completion, the reactionmixture was cooled to r.t., diluted with Et2O (80 mL), and filteredthrough a short pad of Celite (approx. 2 in × 2 in × 2 in) that hadbeen wetted with Et2O to remove metal salts. The reaction vesselwas washed with Et2O (2 × 40 mL) and the washings were thenpassed through the filter. The combined filtrates were transferred toa separatory funnel and washed with aq 1 M NaOH (200 mL). Abrown emulsion formed in the separatory funnel during the workupthat slowly separated. Care was taken to keep the brown emulsion with the organics. Once separated, the aqueous layer was extractedwith additional Et2O (3 × 150 mL). The combined organic extracts and brown emulsion were washed with brine (500 mL). Again carewas taken to keep the brown emulsion with the organics. The organicswere dried with copious amounts of MgSO4. The solid dryingagent was removed by filtration, ground into a fine powder, andwashed with additional Et2O (3 × 150 mL). The filtrate was evaporated to dryness to give 3a (3.57 g) as faintly yellow crystals in 90percentyield. This material was judged analytically pure by NMR and combustion analysis. If necessary the product can be further purified bysublimation (140 °C/300 mtorr).In this example, following Example 1, the synthesis of 4, 4′-di-tert-butyl-2, 2′-bipyridine was investigated. In this example, the synthesis was performed through the reaction of 4-tert-butylpyridine with SD at low concentrations in THF. 4-tert-Butylpyridine (0.5 mmol) was reacted with SD in an amount of molar equivalents with respect to 4-tert-butylpyridine as shown in FIG. 2 in THF. The usage amounts of THF, the reaction temperatures and the reaction times were set as shown in FIG. 2, and the synthesis was performed in the same manner as in Example 1. After the reaction, in the same manner as in Example 1, the production amounts of 4, 4′-di-tert-butyl2, 2′-bipyridine (Compound 2), which was the target reaction product, and 4-tert-butyl-1, 4-dihydropyridine (Compound 1) and 4, 4′, 4″-tri-tert-butyl-2, 2′:6′, 2″-terpyridine (Compound 3), which were the possible reaction by-products, were measured, and their yields were calculated. The recovery rate of the unreacted 4-tert-butylpyridine was calculated in the same manner. The results are summarized in FIG. 2. It is found from these results that when 4-tert-butylpyridine (0.5 mmol) was reacted with SD in an amount of 1 to 2 mol equivalents with respect to the 4-tert-butylpyridine in 2 to 4 ml of THF at 25 to 50° C. for 1 to 24 hours, the 4, 4′-di-tert-butyl-2, 2′-bipyridine compound was obtained with a high yield in all of the cases. In particular, when 0.5 mmol 4-tert-butylpyridine was reacted with SD in an amount of 1 mol equivalent with respect to the 4-tert-butylpyridine in 2 ml of THF at 50° C. for 1 to 6 hours, the 4, 4′-di-tert-butyl-2, 2′-bipyridine compound was obtained with a high yield without the generation of reaction by-products. In addition, when 0.5 mmol 4-tert-butylpyridine was reacted with SD in an amount of 1 mol equivalent with respect to the 4-tert-butylpyridine in 4 ml of THF at 25° C. for 6 hours, the 4, 4′-di-tert-butyl-2, 2′-bipyridine compound was obtained with a high yield without the generation of reaction by-products. It was found that when SD in an amount of 2 mol equivalents was used, the yield decreased compared with the case of 1 mol equivalent, and the material balance also decreased. It was also found from comparison with that the lower the concentrations of 4-tert-butylpyridine and SD were with respect to THF, the higher the yield was.

Molecular Weight:268.4
XLogP3:4.8
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:3
Exact Mass:268.193948774
Monoisotopic Mass:268.193948774
Topological Polar Surface Area:25.8
Heavy Atom Count:20
Complexity:278
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes