Functionalization of saturated hydrocarbons

Recent achievements in intermolecular sp3 C–H bond functionalization of organic compounds by superelectrophilic trihalomethyl metal complex

“…Complex CBr 4 ·2AlBr 3 displayed the breaking activity over all known protic and aprotic systems including the strongest superacids [32]. The reactions of carbonylations in the presence of polyhalomethane based superelectophiles allowed the selective syntheses of the corresponding carboxylates from alkanes C 2 [44], C 3 [45], C 4 −C 5 [46] n-Alkanes C 6 −C 10 were selectively transformed into the corresponding esters of carboxylic acids of the neostructure with the same number of C atoms in alkyl group as in the initial alkane [47]. Selective carbonylations of C 5 [48], C 6 , C 7, C 8 cycloalkanes (and well as their homologues) [49], norbornane, trimethylenenorbornane, adamantane, and 1,3-dimethyladamantane were also described [32b,50].…”

Superacid‐Catalyzed Reactions

“…The one-step double functionalization of aromatics-that is, alkylation and acylation-can be accomplished with alkanes or cycloalkanes (in large excess) using the aprotic organic superacids RCO þ Al 2 X 7 À (R ¼ alkyl, aryl, X ¼ Cl, Br) 391 Fries rearrangement-that is, the transformation of phenolic esters to isomeric hydroxyphenyl ketones-is related to Friedel-Crafts acylations. 392,393 Olah et al 394 have found a convenient way to perform the Fries rearrangement of a variety of substituted phenolic esters in the presence of Nafion-H in nitrobenzene as solvent [Eq.…”

Low-temperature functionalisation of alkanes and cycloalkanes by 'classical' and 'non-classical' (superacidic) Friedel–Crafts complexes

“…Ionic bromination of n-alkanes and cycloalkanes catalysed by the AcBr • 2AICI3 complex and AICI3 in CH 2 C1 2 at 0 °s tudy 78 ). Overall yield of monobromides (%, relative to Ct) 54 Both schemes include stages in which the catalyst is regenerated.…”

“…The reaction with isobutane affords only one isomer, 2-bromo-4-terf-butylacetophenone. 86 Apparently, the /wa-bromo-fer*-butylbenzene formed initially isomerises into the more stable /wefa-isomer in the presence of a strong aprotic superacid. The acylation of the meta-isomer into the para-position with respect to the tert-butyl group gives rise to the reaction product observed.…”