Carbon-oxygen single bond formation

The formation of carbon-oxygen single bonds via the attack of an alkoxide on an alkyl halide, (Williamson ether synthesis) is an extremely important reaction that... 

However, we must recognize that the large driving force for this reaction comes from two sources (1) the formation of the carbon-oxygen single bond—Reaction 1—which is exothermic by about 28 kcal. This initially... 

As before, R indicates that the two R groups can be the same or different. The process of ester formation is called esterification, and the carbonyl carbon-oxygen single bond of the ester group is called the ester linkage ... 

No unusual initiators, such as transition metal complexes or heterogeneous catalysts, are needed for perhaloacetaldehyde polymerizations, the polarization of the carbonyl group of the aldehyde monomer is well defined and does not cause the formation of head to head linkages in the polymer. The shorter carbon oxygen single bond (1.43 A) which is formed by ring opening of the carbonyl double bond (1.21 A) has a beneficial effect for the formation of a helical structure for the isotactic polymer and should, consequently, favor the formation of isotactic polymer. 

The SNl reactivity of a-haloal kanoic acids is particularly low. This is reasonable because formation of a cationic center at the a carbon should be difficult, because of the positive character of the carbonyl carbon. Furthermore, little, if any, help could be expected through electron delocalization because the corresponding valence-bond structure has a positive, single-bonded oxygen ... 

In the course of formation of the relatively stable or fast decomposing 377 (equation 224) the [14C]-carbonyl double bond is transformed into a single [14C]-carbon-oxygen bond, if the P—O bond formation in TS is much more advanced than... 

Two pathways are observed for nucleophile addition to 48 in water (Scheme 49) (i) uncatalyzed nucleophile addition to form the oxygen anion 48 that undergoes rapid protonation (ii) specific acid-catalyzed nucleophile addition. The SDIE on the specific acid-catalyzed addition of solvent and bromide anion to 48 are kH/kD = 0.68 and 1.0, respectively, for reactions in 50/50 (v/v) water trifluoroethanol,67 but a smaller SDIE of kH/kD = 0.41 is observed for the specific acid-catalyzed addition of an aqueous solvent to l.52 The larger SDIE for acid-catalyzed addition of Br to 48 is consistent with a concerted reaction mechanism, in which protonation of oxygen and carbon-bromine bond formation occur in a single step with a rate constant kHBr (Scheme 49). 

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