Cycloalkanes, acylation

Me2N(CH2)mNMe2 (Fig. 16) and that for the formation of N-tosylaza-cycloalkanes [9] (Fig. 10). We have also pointed out (p. 49) that the effect of chain length on the ease of closure of [11] by intramolecular acylation of the... 

Irradiation of methylcyclopropylketone (Formula 311) causes isomerization to 3-penten-2-one (Formula 312) (124). This reaction appears to be limited to acyl cyclopropanes, since acyl cycloalkanes with larger rings undergo photochemical fission to acyl radicals and cycloalkyl radicals (105). The photoisomerization of the bicyclic ketone (Formula 313) to Formula 314 (125) is analogous to the isomerization of Formula 311. 

Akhrem et al.390 have reported a unique method for the acylation of aromatics. When alkanes and cycloalkanes (propane, butane, cyclopentane, cyclohexane) are treated with CBr4-2AlBr3 in the presence of carbon monoxide, the intermediate acyl cations react with aromatic silanes to yield acylated products by desilylative acylation [Eq. (5.151)]. The ipso-substitution of trimethylsilane takes place regioselectively,... 

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+Al2X7 (R = alkyl, aryl, X = Cl, Br)391 [Eq. (5.152)]. However, the method can be used only for benzene and bromobenzene. 

Acetone — and most valuably [2H]6-acetone — to provide acyl adducts with alkenes without interference from reaction with cycloalkanes (Roussis and Fedora 1997) ... 

Cycloalkan--3-acyl-2,3-dihydro-l,3-benzothiazole, erhaltlich aus 2-Amino-thiophe-nol und cyclischen Ketonen sowie nachfolgender Acylierung mit Carbonsaure-anhydriden, spalten in siedendem Dimethylsulfoxid unter Acyl-Wanderung zu 2-[(n +1 )-Oxo-alkyl]-1,3-benzothiazolen317 ... 

Da die Reduktionen der Oxo-Gruppe nach Wolff-Kishner bzw. H u an g - Mi n Ion be-reits in ds. Handb. ausfiihrlich beschrieben sind, wird neben den Verweisen auf die ent-sprechenden Stellen ds. Handb. die neuere Literatur in Tab. 118 (S. 587) beriicksichtigt. Alkane und Cycloalkane aus Ketonen Bd. V/la, S. 251-267 Phenyl-alkane und -cycloalkane aus Phenyl-ketonen Bd. V/la, S. 456-465 Alkyl-phenole aus Acyl-phenolen Bd. VI/lc, S. 1067 Methyl-phenole aus Phenol-aldehyden Bd. VI/lc, S. 1071 Alkane aus AJdehyden Bd. VII/1, S. 491 Alkene aus Carbonyl-olefinen Bd. V/lb, S. 629—631. 

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