Carboxylic esters with organometallic

Other organometallic reagents can be used to convert alkyl halides to carboxylic acid derivatives. Benzylic halides were converted to carboxylic esters with CO in the presence of a rhodium complex, ether a borate ester B(OR )3,... 

Coupling of Organometallic Reagents With Carboxylic Esters... 

For a list of preparations of ketones by the reaction of organometallic compounds with carboxylic esters, salts, anhydyrides, or amides, with references, see Ref. 568, pp. 685, 693. 

Coupling of Organometallic Reagents with Carboxylic Esters Alkyl-de-acyloxy-substitution... 

Coupling of Organometallic Compounds with Aryl Halides, Ethers, and Carboxylic Esters Alkyl-de-halogenation. etc. 

Labelling of proteins and peptides with CpRe(CO)3 fragments can be made by peptide bond formation with the carboxylic acid Re(CpCOOH)(CO)3 or by acylation of free amine groups with organometallic succinimidyl esters. 

The Conversion of Anhydrides, Carboxylic Esters, or Amides to Ketones With Organometallic Compounds... 

The Hammick reaction ipso substitution by an electrophile of a carboxylic group under decarboxylation conditions) with pyridazine-3-carboxylic acid is not very successful, but it is considerably improved by the use of the TMS ester. Thus, trimethylsilyl pyridazine-3-carboxylate reacts with aldehydes to give, probably via an ylide, good yields of TMS protected alcohols (Scheme 50). The trimethylsilyloxy product is readily desilylated, so this process is equivalent to the reaction of a 3-pyridazinyl organometallic reagent with an aldehyde <88T328i>. 

The 2-sulfonyloxaziridine (57) is a more selective oxidant than peracids. The reagent has been employed in the oxidation of sulfides to sulfoxides, disulfides to thiolsulfinates, selenides to selenoxides, thiols to sulfenic acids, organometallic reagents to alcohols and phenols, ketone and ester enolates to a-hydroxycarbonyl compounds (equation 31)41. The oxidation of chiral amide enolates gives optically active a-hydroxy carboxylic acids with 93-99% enantiomeric excess42. 

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