CYCLOHEXANOL, 1-ETHYNYL

In a 1-1. three-necked round-bottomed flask, equipped with a sealed stirrer, a reflux condenser, a thermometer, and a dropping funnel, is dissolved 5 g. of mercuric oxide (Note 1) in a solution of 8 ml. of concentrated sulfuric acid and 190 ml. of water. The solution is warmed to 60°, and 49.7 g. (0.40 mole) of 1-ethynyl-cyclohexanol (Note 2) is added dropwise over a period of 1.5 hours. After the addition has been completed, the reaction mixture is stirred at 60° for an additional 10 minutes and allowed to cool. The green organic layer which settles is taken up in 150 ml. of ether, and the aqueous layer is extracted with four 50-ml. portions of ether (Note 3). The combined ethereal extracts are washed with 100 ml. of saturated sodium chloride solution (Note 4) and dried over anhydrous sodium sulfate. The drying agent is removed, the ether is evaporated, and the residue is distilled under reduced pressure through a 15-cm. column packed with glass helices. The 1-acetylcyclohexanol is collected at 92-94°/15 mm. as a colorless liquid, 1.4670, dl5 1.0248 (Note 5). The yield is 37-38 g. (65-67%). 

The reaction is highly dependent on the alkyne used. When structurally simple 3-hydroxy alkynes such as propargyl alcohol are used, acceptable yields of the addition products are obtained, whereas reactions with alkynes prone to carbocation formation and rearrangement, such as 1-ethynyl-cyclohexanol, give a complex mixture of products.68,73... 

SYNS CARBAMATE de I ETHIKA LCYCLOHEXANOL (FRENCH) 1-ETHINYLCYCLOHEXYL CARBAMATE 1-ETHINYLCYCLOHEXYL CARBONATE 1-ETHYNYL-CYCLOHEXANOL CARBAMATE D 1-ETHYNYLCYCLO-HEXYL CARBAMATE 1-ETHYNYLCYCLOHEXYL ESTER CARBAMIC ACID ETINAMATE D USAF EL-42 VALAMINA VALAMINETTEN VAL.MID VAIADDATE VOL.AMIN... 

Ethyl Zimate Slurry, Ethyl ZImate . See Zinc d iethy I d ith i ocarbam ate Ethyne. See Acetylene 2-Ethynyl-2-butanol. See Methyl pentynol Ethynyl carbinol. SeePropargyl alcohol Ethynyl cyclohexanol. See 1-Ethynylcyclohexanol 1 -Ethynylcyclohexanol CAS 78-27-3 EINECS/ELINCS 201-100-9 Synonyms Ethynyl cyclohexanol 1-Ethynyl-1-cyclohexanol 1-Ethynylcyclohexan-1-ol Empincal C8H12O Formula HC=CC6HioOH Properties Wh. cryst. solid sweet odor sol. in most org. soivs., oxygenated and aromatic soivs. insol. in water m.w. 124.20 dens. 0.967 m.p. 30-31 C b.p. 180C... 

Crosslinked films were prepared from these PDMS-b-PEO copolymers by hydrosilylation reaction between the terminal vinyl groups and multi hydride functional poly(dimethyl-co-methylhydride siloxane) (9), which was a commercial sample from Bayer (CA 730). A Si-H/vinyl ratio of 3 was used. Again Pt(0) was used as a catalyst and ethynyl cyclohexanol as an inhibitor, which prohibited curing before raising the temperature to 115 °C. 

Ethynyl caibinols on heating with formic acid are isomerized to olefinic ketones for example, isohexylmethylethynylcarbinol is taken to 3,7-dimethyl-3-octen-2-one (48%) and 1-ethynyl-1-cyclohexanol to 1-acety 1-1-cyclohexene (70%). Small amounts of unsaturated aldehydes may contaminate the product. 

Gore [30] has found a strong temperature and solvent effect on the reaction of methylmagnesium iodide with ethynyl-l-cyclohexanol. Indeed, the 8N2-coupled compound was obtained as the major product when the reaction was performed in THF under reflux (8n2/8n2 = 95 5), whereas the 8n2 product (allenic derivative) was obtained in ether at low temperature (8 278 2 = 40 60 at 0°C, and 0 100 at — lO C). 

Pd(OAc)2 (47.35 % Pd) was purchased from Degussa. The compounds 4-iodo-toluene, n-butyllithium (1.6 M in hexane), 3-methyl-l-pentyn-3-ol, 2-butyne-l,4-diol, phenylacetylene, diphenylacetylene, 1-ethynyl-l-cyclohexanol and 2-methyl-... 

Isomerization of ethynylcarbinols. Rupe12 first observed that ethynylcarbinols when refluxed in formic acid (90%) are isomerized to unsaturated carbonyl compounds, which he considered to be aldehydes. Chanley13 later investigated the reaction in detail and found that the predominant product is an a,/ -unsaturated ketone. Thus 1-ethynyl-l-cyclohexanol (1) is converted mainly into 1-acetyl-l-cyclohexene (2), with onLy traces of (3) being formed. 

Ethynyl-1-cyclohexanol 1-Ethynylcyclohexan-I-0I. See 1-Ethynylcyclohexanol Ethynyidimethyl carbinol. See Methyl butynol Ethynyl methanol. See Propargyl alcohol Ethyolene bis (thioglycolate). See Glycol dimercaptoacetate... 

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