Aryl alcohols, synthesis with

General procedure for the reaction of an o-substituted aryl iodide with an allylic alcohol. Synthesis of biphenyls containing an oxoalkyl chain. 

Flynn et al., also described the synthesis of the fused indoles [73]. The o-iodotrifluoroacetanilide 110 was coupled to aryl alkyne 111 under Sono-gashira conditions followed by subsequent reaction with aryl iodide, 107 with gaseous carbon dioxide produced the fused indole 158. Lewis acid dealkylation with aluminum trichloride produced the deprotected alcohol 159. 

A common intermediate in the synthesis of benzo[c]phenanthridines is the 2-aryl-l-tetralone, which provides rings A, B, and D of the alkaloid nucleus. In 1973, two independent research groups reported the synthesis of nitidine via the 3,4-dihydro-2-(3,4-dimethoxyphenyl)-6,7-methylenedioxy-(2/7)-naphthalone 29 (Scheme 2). The synthesis of this intermediate was arrived at by two different routes. Kametani ei al. (73JHC31) reduced 3-(3,4-methylenedioxyphenyl)proprionate 21 to the corresponding alcohol 22 with lithium aluminium hydride, which was then converted to the chloride 23 with thionyl chloride. After production of the nitrile 24 by reaction with sodium cyanide and subsequent hydrolysis to the carboxylic acid 25, Friedel-Crafts cyclization of the acid chloride 26 afforded the tetralone intermediate 27. Reaction with l-bromo-3,4-dimethoxybenzene 28 in the presence of sodium amide yielded the tetralone intermediate 29 in an overall yield of 4%. 

Athene synthesis. Alcohols can be alkylated or arylated by treatment with organolithium compounds and 1 (equation 1). The main interest in this synthesis is the reaction of allylic alcohols to form alkenes. The reaction is regioselective and stereoselective (inversion of configuration). 

The main drawback in Sharpless epoxidation is that the substrate must bear a functional group to achieve the precoordination required for high enantioselec-tivity (as in the case of allyl alcohol). This restriction is not applicable to the epoxidation of alkyl- and aryl-substituted olefins with manganese complexes of chiral Schiffs bases as catalysts. Very high enantioselectivities can be obtained in these reactions (Jacobsen, 1993). The most widely used catalysts that give high enantioselectivity are those derived from the Schiff bases of chiral diamines such as [SiS] and [RR] 1,2-diphenylethylenediamine and [SS] and [RR] cyclohexyl-1,2-diamine. An example is the synthesis of cromakalim. 

When allylic alcohols are used as an alkene component in HR, elimination occurs from an oxygen-bearing carbon, and aldehydes or ketones are obtained, rather than jS-arylated allylic alcohols [68,69]. The reaction of methallyl alcohol (113) with a halobenzene is a good synthetic method for dihydro-2-methylcinnamaldehyde, an important fragrant compound 114. The allylic alcohol 115 is not formed. An intramolecular version of the aldehyde formation was applied to the preparation of the key intermediate 117 from 116 in the total synthesis of saponaceolide [70]. 

In 1967, Takahashi and Tsuji [61] reported that carbonylation of substituted azobenzene in protic solvents such as alcohols or water proceeded smoothly under mild conditions to afford 2-aryl-3-indazolinones with separation of metallic palladium in a high yield, as shown in Eq. (7.33). Hence, the reactions are a very good synthetic method for the synthesis of substituted 2-aryl-3-indazolinones 7.39. 

The (SIPr)Pd(cinnamyl)Cl (SlPr= l,3-bis(2,6-diisopropyl phenyl)-4,5-dihydro imidazol-2-ylidene) catalysed anaerobic oxidation of aryl/alkyl, aryl/aryl, and alkyl/ alkyl secondary alcohols to the corresponding ketones in high yields has been achieved using aryl chlorides in toluene with f-BuONa. Domino Pd-catalysed synthesis of a-arylated ketones from secondary aryl alcohols in very good yields was also reported. " ... 

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