Evaporation in vacuum

DlmethylpyrazoM -yl)pentane-2,4-dlone (3). To a stirred suspension of diacetyl hexanedione 1 (2.0 g, 10 mmoO in boiling ElOH (SO mL) was added hydrazine hydrate 2 (0.6 mL). The clarified (charcoal) hot solution was evaporated in vacuum arxi the oily residue was crystallized from water to afford 0.9 g of 3 (4614), mp 134-140°C. 

The crude base is purified by converting 2g of base in toluene (3.3mL) into the acetate salt by heating at 65-70 with 0.46g of AcOH and the crystals are collected and dried (0.96g from two crops m 141-143 ). The acetate salt is dissolved in warm H2O, basified with aqueous NaOH and extracted with C6H6. The dried extract (MgS04) is evaporated in vacuum leaving a viscous oil which crystallises and can be distd. [Gottstein and Cheney J Org Chem 30 2072 1965.] The picrate has m 234-236 (from aq MeOH), and the formate has m 147-148° (from heptane). 

The solution was filtered and evaporated in vacuum over concentrated sulfuric acid. The sodium salt is then obtained as a creamy white water-soluble solid. Glycyrrhetinic acid is obtainable from licorice root. 

A solution or dispersion consisting of 20.1 g (0.1 mol) of 7-chloro-p-fluorobutyrophenone, 19.8 g (0.2 mol) of 4-methylpiperidine end 0.1 g of potassium iodide in 150 ml toluene is heated in a seeled gless tube for 15 hours at 100°C to 110°C. The potassium iodide and the 4-methylpiperidine hydrochloride formed in the reaction are separated by filtration and the solvent removed from the filtrate by evaporation In vacuum on a steam bath. The residue is distilled and the fraction obtained at 120°C to 125 0 and at a pressure lower than 0.1 mm Hg is collected. The basa Is dissolved in ether and the 4-fluoro-7-(4-methylpiperidino)-butyro-phenone precipitated as the hydrochloride. The reaction product is purified by recrystallization in ethanol/ether. 

In Section 13.2, we introduce the materials used in OLEDs. The most obvious classification of the organic materials used in OLEDs is small molecule versus polymer. This distinction relates more to the processing methods used than to the basic principles of operation of the final device. Small molecule materials are typically coated by thermal evaporation in vacuum, whereas polymers are usually spin-coated from solution. Vacuum evaporation lends itself to easy coaling of successive layers. With solution processing, one must consider the compatibility of each layer with the solvents used for coating subsequent layers. Increasingly, multilayered polymer devices arc being described in the literature and, naturally, hybrid devices with layers of both polymer and small molecule have been made. 

The radiochemical oxidation of PS in a chloroform solution is accompanied by its destruction and formation of products of styrene oxidation, namely, benzaldehyde and styrene oxide [136]. The radiochemical yield of these products was equal to the radiochemical yield of PS macromolecule cleavages. Butyagin [137] analyzed the products of decomposition of the peroxyl radicals of PS and polyvinyIcyclohexane. Alkyl macroradicals were produced mechano- or photochemically, volatile products were evaporated in vacuum, and alkyl radicals were converted into peroxyl radicals using labeled lsO. Peroxyl radicals were then... 

Olivetol 4.74 g (or equimolar amount of analog), 4.03 g (+) cis or trans p-methadien (2,8)-ol-l (the racemic compound can be used but yield will be one-half), 0.8 g p-toluenesulfonic acid in 250 ml benzene reflux two hours (or use 0.004 Moles trifluoracetic acid and reflux five hours). Cool, add ether, wash with NaHC03 and dry, evaporate in vacuum/to get about 9 g of mixture (can chromatograph on 3 50 g silica gel-benzene elutes the THC benzene ether 98 2 elutes an inactive product then benzene ether 1 1 elutes unreacted olivetol evaporate in vacuum to recover olivetol). 

M (+)-trans-2-carene oxide (2-epoxycarene), 1M olivetol or analog, 0.05 M p-toluenesulfonic acid in 10L benzene reflux two hours and evaporate in vacuum (or can separate the unreacted olivetol as above) to get about 30% yield THC. Olivetol can also be separated as described below. For synthesis of 2-epoxycarene (A4 carene oxide) from A4 carene (preparation given later) see p-methadieneol preparation (Method 2). 3-carene oxide gives 20% yield of AH6) THC. 

M pulegone, 1M olivetol of analog, 0.3 M POCl3, reflux four hours in 1 L benzene and evaporate in vacuum or pour into excess saturated NaHC03 and extract with dilute NaOH to recover unreacted olivetol. Dry, and evaporate in vacuum the benzene layer to get the THC. 

NaHC03 and recrystallize from acetonitrile. Dissolve 4.3 g (T) in 30 ml anisole and add 0.1 M methyl Mgl in 50 ml anisole. Stir 12 hours and evaporate in vacuum or acidify with sulfuric acid, neutralize with NaHC03 and filter wash to get 2.4 g N-benzyl analog of THC. For other N-analogs of unknown activity see JOC 3(5,2995(1968). Recover unreacted olivetol as usual. 

I). 4.5g(I), 150 ml benzene add dropwise to a solution prepared from 7.8 g Mg, 18 ml methyl iodide, and 90 ml ether. Reflux 20 hours and add 45 ml saturated NH4CI. Separate the organic layer and extract the aqueous phase with benzene. Combine the organic layer and benzene and dry, evaporate in vacuum to get the THC analog. 

M olivetol or analog, 1M citral in 10% BF3 etherate in benzene about eight hours at 5-10° C. Extract unreacted olivetol with dilute NaOH and evaporate in vacuum the ether to get about 20% yield of the trans THC, and 20% of the cis THC which can be converted to the active trans isomer by reacting with BBr3 in methylene chloride at -20° C for Vh hours. (TL 4947(1969)). Alternatively, the reaction can be carried out in 1 % BF3 etherate in methylene chloride to get 20% THC. 

Alternatively, to 150 ml ethylene diamine add portionwise with stirring at 110° C under Argon or N2, 5.3 g Li metal after one hour add dropwise 110 g (+) A3 carene. After one hour cool to 4° C and add water. Extract with ether, wash the ether five times with water and dry, evaporate in vacuum to get 100 g of a mix containing about 40% (+) A4 carene (can separate by fractional distillation). 

A4 carene can also be obtained from A3 carene as follows (JCS (C) 46(1966)) Dissolve 1 g A3 carene in 50 ml propionic acid and heat at a suitable temperature (e.g., one-half hour at room temperature may do) in presence of /2g Palladium-Carbon catalyst (5%) in ethanol and filter, evaporate in vacuum (can distill 63.5/19.5). See J.Soc. Cosmet. Chem. 22,249(1971) for a review of (+) A3 carene chemistry. 

To 136 g A4 carene in 330 ml methylene chloride and 120 g anhydrous sodium acetate, add dropwise with vigorous stirring ir an ice bath, 167 g of 50% peracetic acid and continue stirring for ten hours. Heat to boiling for two hours, cool, wash with water, sodium carbonate, water, and dry, evaporate in vacuum the methylene chloride to get about 100 g p-menthadieneol. Apparently (CA... 

Reduce 3,5-dimethoxybenzoic acid with lithium aluminum hydride to 3,5-dimethoxybenzyl alcohol (I), to 10.5 g (I) in 100 ml methylene chloride at 0° C add 15 g PBr3 warm to room temperature and stir for one hour. Add a little ice water and then more methylene chloride. Separate and then dry, evaporate in vacuum the methylene chloride. Add petroleum ether to precipitate about 11.5 g of the benzyl bromide (II). To 9.25 g (II), 15 g Cul, 800 ml ether at 0° C, add butyl (or other alkyl)-Li (16% in hexane), and stir for four hours at 0° C. Add saturated NH4C1 and extract with ether. Dry and evaporate in vacuum the ether (can distill 100/0.001) to get about 4.5 g olivetol dimethyl ether (HI) or analog. Distill water from a mixture of 90 ml pyridine, 100 ml concentrated HC1 until temperature is 210° C. Cool to 140 0 C and add 4.4 g (III) reflux two hours under N2. Cool and pour into water. Extract with ether and wash with NaHC03. Make pH 7 and dry, evaporate in vacuum to get 3.8 g olivetol which can be chromatographed on 200 g silica gel (elute with CHC13) or distill (130/0.001) to purify. 

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