Summary Flow Charts -- Carbonyl Compound Chemistry

A pair of summary flow charts closes the unit, tying together the whole chapter's preparation and reaction network around a single central node, 'Carbonyl Compounds'. METHODS OF PREPARATION (fanning in): alkenes, by ozonolysis; alkynes, by dilute H2SO4/HgSO4 hydration (gem-dihalides forming as an unstable intermediate, hydrolysed onward); alcohols (R-OH), by Cu-catalysed dehydrogenation or by PCC/K2Cr2O7 oxidation; calcium carboxylate salts, (RCOO)2Ca, by dry distillation; alkyl cyanides, R-C#N, by Stephen's reaction (SnCl2/HCl then hydrolysis); and acid chlorides, RCOCl, by Rosenmund's reduction (H2/Pd-BaSO4). CHEMICAL PROPERTIES (fanning out from the same central carbonyl): HCN gives a cyanohydrin, R2C(OH)(CN); NaHSO3 gives the bisulphite addition compound, R2C(OH)(SO3Na); an ammonia derivative, H2N-Z, gives the imine-type product R2C=N-Z; ESTERS are given by ALL aldehydes specifically via the Tischenko reaction (a base-free, aluminium-alkoxide-catalysed disproportionation of an aldehyde directly to its own ester, distinct from -- and not detailed in the main chapter text as -- the Cannizzaro-family reactions); carbonyl compounds WITH an alpha-hydrogen give the Aldol reaction, while carbonyl compounds WITHOUT an alpha-hydrogen instead give the Cannizzaro reaction; Grignard reagents (RMgX) then H3O+ give alcohols; catalytic reduction (LiAlH2, i.e. LiAlH4, delivering hydride) gives an alcohol; the Clemmensen reduction (Zn-Hg/conc. HCl) gives the alk …