4-ETHYNYLBENZYL ALCOHOL 97

4-ETHYNYLBENZYL ALCOHOL 97 Property

Melting point:

40-44 °C(lit.)

Boiling point:

239.6±23.0℃ (760 Torr)

Density 

1.08±0.1 g/cm3 (20 ºC 760 Torr)

Flash point:

>230 °F

storage temp. 

Keep in dark place,Sealed in dry,Room Temperature

form 

powder to crystal

pka

14.13±0.10(Predicted)

color 

White to Orange to Green

InChI

InChI=1S/C9H8O/c1-2-8-3-5-9(7-10)6-4-8/h1,3-6,10H,7H2

InChIKey

QCZORVSTESPHCO-UHFFFAOYSA-N

SMILES

C1(CO)=CC=C(C#C)C=C1

Safety

Hazard Codes 

Xn

Risk Statements 

22-36-42/43

Safety Statements 

26-36

WGK Germany 

2

HS Code 

2906290090

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H302Harmful if swallowed

H319Causes serious eye irritation

Precautionary statements

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P270Do not eat, drink or smoke when using this product.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P301+P312IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P337+P313IF eye irritation persists: Get medical advice/attention.

4-ETHYNYLBENZYL ALCOHOL 97 Chemical Properties,Usage,Production

Uses

• 4-Ethynylbenzyl alcohol can be used in the synthesis of platinum-acetylide dendrimers, rotaxanes and arylacetylenes.
• It was employed in the preparation of arylalkyne-tagged sugars for the photoinduced glycosylation of cysteine-containing peptides.
• It can also act as a precursor to synthesize fluorescent probes via Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction.

Synthesis

General steps: 1. To an anhydrous triethylamine (TEA) solution of (4-bromophenyl)methanol (935 mg, 5 mmol), Pd(PPh3)2Cl2 (175 mg, 0.25 mmol), CuI (48 mg, 0.25 mmol), and P(t-Bu)3 (51 mg, 0.25 mmol) were sequentially added under nitrogen protection. 2. After stirring the reaction mixture for 5 minutes, ethynyltrimethylsilane (980 mg, 10 mmol) was added dropwise. 3. The reaction mixture was microwaved at 130 °C for 4 hours and subsequently cooled to room temperature. 4. The reaction mixture was filtered through diatomaceous earth and the filtrate was concentrated under reduced pressure. 5. The residue was extracted three times with a mixture of ethyl acetate (EtOAc) and water and the organic layers were combined. 6. The organic layer was washed with brine, dried over anhydrous sodium sulfate (Na2SO4), filtered and purified by silica gel column chromatography (petroleum ether/ethyl acetate=4/1) to afford (4-((trimethylmethylsilyl)ethynyl)phenyl)methanol as a brown oil (670 mg, 66% yield). [0633] 1. To a solution of (4-((trimethylmethylsilyl)ethynyl)phenyl)methanol (250 mg, 1.23 mmol) in tetrahydrofuran (THF) was added tetrabutylammonium fluoride (TBAF, 500 mg, 2.45 mmol) in one portion at 0 °C. 2. The reaction mixture was stirred from 0 °C to room temperature for 3 hours. 3. The reaction mixture was concentrated under reduced pressure and the residue was extracted three times with a mixture of ethyl acetate (EtOAc) and water and the organic layers were combined. 4. The organic layer was washed with brine, dried over anhydrous sodium sulfate (Na2SO4), filtered and purified by silica gel column chromatography (petroleum ether/ethyl acetate=4/1) to afford (4-ethynylphenyl)methanol as a brown oil (170 mg, 100% yield). 1H NMR (400 MHz, CDCl3) δ 7.45-7.49 (m, 2H), 7.21-7.26 (m, 2H), 4.69 (s, 1H), 4.65 (s, 2H).

References

[1] Angewandte Chemie - International Edition, 2004, vol. 43, # 29, p. 3814 - 3818
[2] Patent: WO2018/14802, 2018, A1. Location in patent: Paragraph 0364
[3] Patent: WO2008/31157, 2008, A1. Location in patent: Page/Page column 65
[4] Chemistry - A European Journal, 2013, vol. 19, # 29, p. 9452 - 9456
[5] Synthesis (Germany), 2014, vol. 46, # 3, p. 348 - 356