Acyl complexes solvent effects

Diels-Alder reactions, 4, 842 flash vapour phase pyrolysis, 4, 846 reactions with 6-dimethylaminofuKenov, 4, 844 reactions with JV,n-diphenylnitrone, 4, 841 reactions with mesitonitrile oxide, 4, 841 structure, 4, 715, 725 synthesis, 4, 725, 767-769, 930 theoretical methods, 4, 3 tricarbonyl iron complexes, 4, 847 dipole moments, 4, 716 n-directing effect, 4, 44 2,5-disubstituted synthesis, 4, 116-117 from l,3-dithiolylium-4-olates, 6, 826 electrocyclization, 4, 748-750 electron bombardment, 4, 739 electronic deformation, 4, 722-723 electronic structure, 4, 715 electrophilic substitution, 4, 43, 44, 717-719, 751 directing effects, 4, 752-753 fluorescence spectra, 4, 735-736 fluorinated derivatives, 4, 679 H NMR, 4, 731 Friedel-Crafts acylation, 4, 777 with fused six-membered heterocyclic rings, 4, 973-1036 fused small rings structure, 4, 720-721 gas phase UV spectrum, 4, 734 H NMR, 4, 7, 728-731, 939 solvent effects, 4, 730 substituent constants, 4, 731 halo... 

The preceding sections have shown the complexity of solvent effects in the solvolysis of acyl chlorides, and how ambiguities in the role of the solvent, particularly in its apparent reaction order, critically affect the assignment of detailed mechanism. It is the intention in this brief section to point to some of... 

The last example in Table 6.13 is the Friedel-Crafts acylation of naphthalene (CioHg). Substitution is found at both C-1 (C-a) and C-2 (C-P). Presumably, these products form by pathways that are similar to those already examined. However, dramatic solvent effects on the product ratio have been reported and if the acylation is carried out in solvents that can form complexes with ethanoyl chloride (acetyl... 

Scheme 5.2 outlines our design of nucleophilic transacylation catalysts based on crown-complexed alkaline-earth metal ions. By virtue of the acidity-enhancing effect ofthe complexed metal ion, dissociation ofthe proton-ionizable function XH should take place under moderately basic conditions. The metal ion assists acyl transfer from a reactant ester to the catalyst and its subsequent transfer from the acylated catalyst to an external nucleophile (solvent), thus restoring the active form of the... 

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