Search results
Results from the WOW.Com Content Network
Usually, the crossed product is the major one. Any traces of the self-aldol product from the aldehyde may be disallowed by first preparing a mixture of a suitable base and the ketone and then adding the aldehyde slowly to the said reaction mixture. Using too concentrated base could lead to a competing Cannizzaro reaction. [12]
Among the many formylation reagents, particularly important are formic acid and carbon monoxide. [1] A formylation reaction in organic chemistry refers to organic reactions in which an organic compound is functionalized with a formyl group (-CH=O). The reaction is a route to aldehydes (C-CH=O), formamides (N-CH=O), and formate esters (O-CH=O).
In its simplest implementation, base induces conversion of an aldehyde or a ketone to the aldol product. One example involves the aldol condensation of propionaldehyde: 2 CH 3 CH 2 CHO → CH 3 CH 2 CH(OH)CH(CH 3)CHO. Featuring the RCH(OH)CHR'C(O)R" grouping, the product is an aldol. In this case R = CH 3 CH 2, R' = CH 3, and R" = H.
The Wittig reaction or Wittig olefination is a chemical reaction of an aldehyde or ketone with a triphenyl phosphonium ylide called a Wittig reagent.Wittig reactions are most commonly used to convert aldehydes and ketones to alkenes.
Hydroformylation of an alkene (R 1 to R 3 organyl groups (i. e. alkyl-or aryl group) or hydrogen). In organic chemistry, hydroformylation, also known as oxo synthesis or oxo process, is an industrial process for the production of aldehydes (R−CH=O) from alkenes (R 2 C=CR 2).
It is however less reactive than ylides lacking EWGs. For example they usually fail to react with ketones, necessitating the use of the Horner–Wadsworth–Emmons reaction as an alternative. Such stabilized ylides usually give rise to an E-alkene product when they react, rather than the more usual Z-alkene. A "stabilized" Wittig reagent.
The Shapiro reaction or tosylhydrazone decomposition is an organic reaction in which a ketone or aldehyde is converted to an alkene through an intermediate hydrazone in the presence of 2 equivalents of organolithium reagent. [1] [2] [3] The reaction was discovered by Robert H. Shapiro in 1967. [4]
Arndt–Eistert reaction is a series of chemical reactions designed to convert a carboxylic acid to a higher carboxylic acid homologue (i.e. contains one additional carbon atom) Kowalski ester homologation, an alternative to the Arndt-Eistert synthesis. Has been used to convert β-amino esters from α-amino esters through an ynolate ...