Dichloromethane → 4-(1,4-dioxaspiro[4.5]dec-7-en-8-yl)-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrazole

HRID 2047198Notes

Reaction equation

Br[C:2]1[CH:3]=[N:4][N:5]([CH2:7][O:8][CH2:9][CH2:10][Si:11]([CH3:14])([CH3:13])[CH3:12])[CH:6]=1.CC1(C)C(C)(C)OB([C:23]2[CH2:32][CH2:31][C:26]3([O:30][CH2:29][CH2:28][O:27]3)[CH2:25][CH:24]=2)O1.[O-]P([O-])([O-])=O.[K+].[K+].[K+].C(Cl)Cl>C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2].O.O1CCOCC1>[O:27]1[C:26]2([CH2:31][CH2:32][C:23]([C:2]3[CH:3]=[N:4][N:5]([CH2:7][O:8][CH2:9][CH2:10][Si:11]([CH3:14])([CH3:13])[CH3:12])[CH:6]=3)=[CH:24][CH2:25]2)[O:30][CH2:29][CH2:28]1

Participants

Conditions

Temperature: 160 °C

Procedure

To a 10-20 mL microwave vessel was charged 4-bromo-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrazole (0.60 mmol, 166 mg), 4,4,5,5-tetramethyl-2-(1,4-dioxaspiro[4.5]dec-7-en-8-yl)-1,3,2-dioxaborolane (0.84 mmol, 224 mg), K3PO4 (1.80 mmol, 382 mg), PdCl2(dppf).CH2Cl2 (0.06 mmol, 50 mg) and 9:1 Dioxane:H2O (15 mL). The suspension was sonicated to break up salts, flushed with argon, sealed, and heated to 160° C. for 45 minutes in microwave synthesizer. The reaction was concentrated in vacuo, and the residue purified via silica gel chromatography (0% to 60% ethyl acetate in hexanes) to yield 4-(1,4-dioxaspiro[4.5]dec-7-en-8-yl)-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrazole (115 mg, 0.34 mmol, 57% yield) as clear oil.

Workup

customThe suspension was sonicated
customflushed with argon
customsealed
concentrationThe reaction was concentrated in vacuo
customthe residue purified via silica gel chromatography (0% to 60% ethyl acetate in hexanes)

Sources & evidence

ORD record: ord-c488b369631e46db9e313390a4f88f82
Source dataset: uspto-grants-2013_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08591943B2

Reaction notes

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