Acetonyltriphenylphosphonium bromide in organic synthesis: a useful catalyst in the cyclotrimerization of aldehydes

Comparing the Stereoselective Biooxidation of Cyclobutanones by Recombinant Strains Expressing Bacterial Baeyer–Villiger Monooxygenases

“…The crude product was purified via column chromatography (LP/EtOAc = 2/1) and was obtained as a yellow oil. [36] …”

Phosphonium Salt Organocatalysis

“…[43] Hon et al also discovered that acetonyltriphenylphosphonium bromide (14) is an effective catalyst for the cyclotrimerization of aldehyds bearing a variety of functional groups under solvent-free conditions at room temperature (Scheme 15). [44] Scheme 13. Cyanosilylation of aldehydes catalyzed by 13 and selected examples.…”

New Cyclotrimerization of Aldehydes to Cyclopentenone or Tetrahydrofuran Induced by Dibromotriphenylphosphorane

“…Whereas the aldolization of two aldehyde units is fully reported to yield unsaturated aldehydes, [1] the self-reaction of three aldehyde units is documented to generate different families of compounds ( Figure 1): the condensation of aldehydes mediated by bases or Lewis acids [2] or recently by -proline [3] is reported to give unsaturated aldehydes and triketides [Equation (1)]. The cyclotrimerization of aldehydes catalyzed by bromine, [4] acetonyltriphenylphosphonium bromide, [5] and protic or Lewis acids [6] is well known to afford 1,3,5-trioxanes [Equation (2)]. 2-Deoxyribose-5-phosphate aldolase [7] (DERA, EC 4.1.2.4) as well as -proline [3b] are reported to catalyze the tandem aldol condensation of aldehydes to trideoxyhexoses [Equation (3)].…”

“…The self-condensation of propionaldehyde with an ammonium salt is known to lead to cyclopentenone as a byproduct [Equation (4)]. [8] More recently, the first asymmetric self-aldol reaction of acetaldehyde catalyzed by diarylprolinol yielded its trimer acetal [Equation (5)]. [9] Enolizable aldehydes underwent trimerization by the aldol-Tishchenko reaction to produce 1,3-diol monoesters [Equation (6)].…”