Trimethylsilylacetylene → 6-Trimethylsilanylethynylbenzothiazol

HRID 2244114Notes

Reaction equation

[CH3:1][Si:2]([C:5]#[CH:6])([CH3:4])[CH3:3].Br[C:8]1[CH:16]=[CH:15][C:11]2[N:12]=[CH:13][S:14][C:10]=2[CH:9]=1>C(N(CC)CC)C.[Cu]I.[Pd](Cl)Cl.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>[CH3:1][Si:2]([C:5]#[C:6][C:8]1[CH:16]=[CH:15][C:11]2[N:12]=[CH:13][S:14][C:10]=2[CH:9]=1)([CH3:4])[CH3:3]

Participants

Conditions

Temperature: 80 °C

Procedure

Trimethylsilylacetylene (106 ml), copper (I) iodide (0.948 g), and bis(triphenylphosphine) palladium(II) dichloride (1.75 g) were added to 6-bromobenzothiazole (53.3 g) in triethylamine (260 ml), and the mixture was stirred for 2.5 hours at 80° C. After the solvent was evaporated, the resultant residue was loaded on a short column (silica gel; hexane:ethyl acetate=2:1) for elution. The residue from the eluate was recrystallized from a mixed solvent of hexane-ethyl acetate, and consequently, 6-trimethylsilanylethynylbenzothiazole (20.0 g) was obtained as a colorless powder (mp: 104.5-105.0° C.). By repeated subjecting the filtrate to recrystallization repeated (n-hexhane-ethyl acetate), secondary crystals (12.1 g), tertiary crystals (9.68 g), and quaternary crystals (4.61 g) were obtained as a colorless powder.

Workup

customAfter the solvent was evaporated
washthe resultant residue was loaded on a short column (silica gel; hexane:ethyl acetate=2:1) for elution
customThe residue from the eluate was recrystallized from a mixed solvent of hexane-ethyl acetate

Sources & evidence

ORD record: ord-2a31c4b0eacf465781270bd3d2a75f73
Source dataset: uspto-grants-2010_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07678810B2

Reaction notes

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