3,5-Dimethyl-1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole

3,5-Dimethyl-1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole is the borylated analog of 4‑bromo‑3,5‑dimethyl‑1‑THP‑pyrazole and serves as the nucleophilic partner in a broad array of C–C bond‑forming reactions. The crystalline, non‑hygroscopic nature of 3,5-Dimethyl-1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole makes it far easier to handle than the corresponding free N–H boronic acid, which is prone to anhydride formation and decomposition. In parallel synthesis libraries, 3,5-Dimethyl-1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole is used to explore the structure–activity relationships of 4‑substituted pyrazoles in one step from commercially available aryl halides. Cosperpharm verifies the boronate content, residual palladium, and THP integrity of every batch of 3,5-Dimethyl-1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole to ensure consistent coupling yields.

Product Parameters

Product Advantages

1.Ready‑to‑Couple Boronate Ester – Eliminates the need for in‑house borylation; simply combine with an aryl halide, catalyst, and base to form the biaryl.

2.THP‑Protected Pyrazole – The nitrogen is masked, preventing protodeboronation that plagues free N–H pyrazole‑boronic acids.

3.Stable Crystalline Solid – Does not stick to glassware, does not require glovebox handling, and can be stored on the bench for short periods.

4.High Active Boronate Content – ≥98% purity and correct boron stoichiometry mean you are not paying for inactive boroxine or deboronated material.

5.Multi‑Scale Availability – Cosperpharm stocks this compound from 1 g vials for discovery through 5 kg lots for process development.

Synthetic Route

3,5-Dimethyl-1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole is synthesized by palladium‑catalyzed borylation of 4‑bromo‑3,5‑dimethyl‑1‑(THP)‑1H‑pyrazole with bis(pinacolato)diboron (B₂pin₂) in the presence of potassium acetate and Pd(dppf)Cl₂ or Pd(PPh₃)₄ in dioxane at 80–100 °C. After aqueous workup, the crude product is crystallized from heptane/ethyl acetate to remove pinacol‑related impurities, giving the pure boronate ester.

FAQ

Q: Is this compound sensitive to protodeboronation?

A: The pinacol ester is moderately stable to aqueous base, but prolonged heating in water‑rich solvents can lead to some loss. We recommend using the minimum amount of water (2–3 equivalents) in couplings.

Q: Can the THP group be removed in the same pot after coupling?

A: Yes, after completion of the Suzuki step, adding 1 M HCl and stirring for a few hours at room temperature or slightly elevated temperature cleaves the THP group to give the free pyrazole.

Contact Us

To bypass your borylation step and purchase this crystalline coupling partner directly, contact Cosperpharm’s commercial team — we can ship R&D quantities within 48 hours and provide larger lots under a mutually agreed quality agreement.