2-alkyl-2-adamantanol

Tnfluoroacetic anhydnde in a mixture with sulfuric acid is an efficient reagent for the sulfonylation of aromatic compounds [44] The reaction of benzene with this system in nitromethane at room temperature gives diphenyl sulfone in 61% yield Alkyl and alkoxy benzenes under similar conditions form the corresponding diaryl sulfones in almost quantitative yield, whereas yields of sulfones from deactivated arenes such as chlorobenzene are substantially lower [44] The same reagent (tnfluoroacetic anhydride-sulfunc acid) reacts with adamantane and its derivatives with formation of isomeric adamantanols, adamantanones, and cyclic sultones [45]... 

Secondary Alkyl Alcohols. Treatment of secondary alkyl alcohols with tri-fluoroacetic acid and organosilicon hydrides results only in the formation of the trifluoroacetate esters no reduction is reported to occur.1,2 Reduction of secondary alkyl alcohols does take place when very strong Lewis acids such as boron trifluoride126 129 or aluminum chloride136,146 are used. For example, treatment of a dichlo-romethane solution of 2-adamantanol and triethy lsilane (1.3 equivalents) with boron trifluoride gas at room temperature for 15 minutes gives upon workup a 98% yield of the hydrocarbon adamantane along with fluorotriethylsilane (Eq. 10).129... 

Laali et al.234 have developed a method to the highly selective pura-adamantylation of arenes (toluene, ethylbenzene, anisole) with haloadamantanes (1-chloro- and 1-bromoadamantane, l-bromo-3,5,7-trimethyladamantane) and 1-adamantanol promoted by triflic acid in butylmethylimidazolium triflate [BMIM][OTf] ionic liquid. In contrast to reactions mn in 1,2-dichloroethane, little or no adamantane byproduct was detected in [BMIM][OTf. Furthermore, no isomerization of para-tolyladamantane was observed supporting the intramolecular nature of the formation of meta isomers. In competitive experiments with benzene-toluene mixture (1 1 molar ratio), high substrate selectivities were found (kT/kB = 16-17) irrespective of the alkylating agent. This is in sharp contrast to values about unity measured in 1,2-dichloroethane. 

The precise mechanism of these intermolecular reactions is not known. Transient disproportionation processes, although well documented in less acidic media (see below and Section V.A.l), seem unlikely if alkyl cations alone are involved. Two possible explanations for the observed results may be considered. Small amounts of polymeric impurities may be present in the reaction mixture which could serve as a hydride source, catalyzing the intermolecular reaction as indicated in Eq. (16)4°). Alternatively, the intermolecular reactions may result from inefficient mixing during reaction initiation. In this case, unionized alcohols would serve as the hydride source. This latter alternative is consistent with the observation 4°1 that the deuterium in the 1-adamantanol obtained from the rearrangement of 38 is distributed between bridgehead and methylene positions. Unless more than one re-... 

Adamantyl)thiacalix[4]arene was synthesized either by condensation of p- 1 -adamantyl)-phenol with sulfur in the presence of base or alkylation of p-//-thiacalix[4]arene with adamantanol in F3CCO2H <02TL5153>. A new macrotricyclic ligand with an N4S2 donor set has been synthesized from cyclam it was shown to encapsulate lithium and transition metal ions <02CC170>. 

At —40°C and under Ar, (43c) reacts with adamantane to afford 1-adamantanol (56%) and 2-adamantanone (20%). With H2O2 as a terminal oxidant, however, (43a) and its sterically more demanding analogue [Fe(6-Me2-BPMCN)(OTf)2] (44a) catalyzes enantioselective epoxidation and ci5-dihydroxylation of alkene substrates, demonstrating the metal-based nature of this transformation. Apparently, the use of HOOH vs. ROOH significantly alters the pathways adopted by the Fe —OOR (R = alkyl or H) adduct. The origin of such a functional shift needs further clarification. 

Adamantyl iodide reacts with [Co(CN)j] to form [(l-adamantyl)Co -(CN)j] which was isolated as its potassium salt. The anion s stability in neutral or alkaline solution is comparable with that of [MeCo(CN)j] however, it undergoes facile acid-catalysed decomposition to 1-adamantyl cyanide and l-adamantanol. (7i-Cp)Co(PPh3)l2 reacts with cyanide to form [(7c-Cp)Co(PPh3)(CN)2], whereas a similar reaction of [(7i-Cp)Co(CO)l2] gives [(7i-Cp)Co(CN)3] . Alkylation of the anion yields [(7i-Cp)Co(CN)2-(CNMe)] or [(7 -Cp)Co(CNEt)3]2 +. 2o... 

Adapalene, is an RAR selective (P and y) retinoid, marketed by GIRD Galderma, for the topical treatment of acne and psoriasis. It is a stable naphthoic acid derivative prepared by Friedel-Crafts alkylation of p-bromophenol 33 with 1-adamantanol to afford 34 in 86% yield (Scheme 10). Methylation of 34, formation of the organozinc species and nickel-catalyzed cross condensation with methyl 6-bromo-2-naphtiioate, afforded adapalene in 43% yve A. 44,4S)... 

The authors in [54] studied interaetion of spatially constrained 2-(2-hydroxyphenyl)-2-adamantanole with imidazoles. Products of 1-H-alkylation 63, 64 are isolated. 

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