42746-55-4

Upstream product

• 67-56-1 methanol 
• 4962-45-2 2-bromo-1-phenyl-propan-1-ol 
• 124-41-4 sodium methylate 
• 637-50-3 1-phenylpropene 
• 2114-00-3 2-bromo-1-phenyl-1-propanone 
• 56819-81-9 1-phenyl-2-phenylsulfanylpropan-1-ol 
• 6493-83-0 2-methoxy-1-phenyl-propan-1-one 
• 4079-52-1 methoxymethyl phenyl ketone 

Downstream Products

• 135271-19-1 lithium syn-2-methoxy-1-phenyl-1-propoxide 
• 103-79-7 1-phenyl-acetone 
• 36391-93-2 1,2-dimethoxy-1-phenylpropane 

Relevant academic research and scientific papers

Competition Between Cα-S and Cα-Cβ Bond Cleavage in β-Hydroxysulfoxides Cation Radicals Generated by Photoinduced Electron Transfer?

A kinetic and product study of the 3-cyano-N-methyl-quinolinium photoinduced monoelectronic oxidation of a series of β-hydroxysulfoxides has been carried out to investigate the competition between Cα-S and Cα-Cβ bond cleavage within the corresponding cation radicals. Laser flash photolysis experiments unequivocally established the formation of sulfoxide cation radicals showing their absorption band (λmax ≈ 520?nm) and that of 3-CN-NMQ? (λmax ≈ 390?nm). Steady-state photolysis experiments suggest that, in contrast to what previously observed for alkyl phenyl sulfoxide cation radicals that exclusively undergo Cα-S bond cleavage, the presence of a β-hydroxy group makes, in some cases, the Cα-Cβ scission competitive. The factors governing this competition seem to depend on the relative stability of the fragments formed from the two bond scissions. Substitution of the β-OH group with -OMe did not dramatically change the reactivity pattern of the cation radicals thus suggesting that the observed favorable effect of the hydroxy group on the Cα-Cβ bond cleavage mainly resides on its capability to stabilize the carbocation formed upon this scission.

Tandem Acid/Pd-Catalyzed Reductive Rearrangement of Glycol Derivatives

Herein, we describe the acid/Pd-tandem-catalyzed transformation of glycol derivatives into terminal formic esters. Mechanistic investigations show that the substrate undergoes rearrangement to an aldehyde under [1,2] hydrogen migration and cleavage of an oxygen-based leaving group. The leaving group is trapped as its formic ester, and the aldehyde is reduced and subsequently esterified to a formate. Whereas the rearrangement to the aldehyde is catalyzed by sulfonic acids, the reduction step requires a unique catalyst system comprising a PdII or Pd0 precursor in loadings as low as 0.75 mol % and α,α′-bis(di-tert-butylphosphino)-o-xylene as ligand. The reduction step makes use of formic acid as an easy-to-handle transfer reductant. The substrate scope of the transformation encompasses both aromatic and aliphatic substrates and a variety of leaving groups.

Aerobic Photooxidative Synthesis of β-Alkoxy Monohydroperoxides Using an Organo Photoredox Catalyst Controlled by a Base

Transition-metal-free synthesis of β-alkoxy monohydroperoxides via aerobic photooxidation using an acridinium photocatalyst was developed. This method enables the synthesis of some novel hydroperoxides. The peroxide source is molecular oxygen, which is cost-effective and atomically efficient. Magnesium oxide plays an important role as a base in the catalytic system.

Generation of hafnium hydride and its application to chemo- and diastereoselective reactions

Hafnium hydride was generated by the transmetalation between Bu 3SnH and HfCl4 using either THF or EtCN as the solvent. This process effectively reduced aldehydes, aldimines, ketones, and esters. In the hafnium hydride reduction of α-alkoxyketones, the diastereoselectivity was dependent on whether THF or EtCN was used as the solvent. Georg Thieme Verlag Stuttgart.

Diastereoselectivity in the reduction of α-oxy- and α-amino-substituted acyclic ketones by polymethylhydrosiloxane

Diastereoselectivity in the reduction of α-alkoxy-, α-acyloxy-, and α-alkylamino-substituted ketones with polymethylhydrosiloxane (PMHS) in the presence of fluoride ion catalysis was investigated. High syn-selectivity was observed in the reduction of α-alkoxy, α-acyloxy, and α-dialkylamino ketones. Reduction of α-monoalkylamino ketone proceeded in anti-selective manner with moderate selectivity. The observed selectivity is explained based on Felkin-Anh and Cram-chelate models.

Product studies and laser flash photolysis on alkyl radicals containing two different β-leaving groups are consonant with the formation of an olefin cation radical

1-Bromo-2-methoxy-1-phenylpropan-2-yl (3) and 2-methoxy-1-phenyl-1-diphenylphosphatopropan-2-yl (4) were generated under continual photolysis from the respective PTOC precursors in a mixture of acetonitrile and methanol. The radicals undergo heterolytic fragmentation of the substituent in the β-position to generate the olefin cation radical (5). Z-2-Methoxy-1-phenylpropene (15) is the major product formed in the presence of 1,4-cyclohexadiene, and is believed to result from hydrogen atom transfer to the oxygen of the olefin cation radical, followed by deprotonation. Laser flash photolysis experiments indicate that reaction between 5 and 1,4-cyclohexadiene occurs with a rate constant of ～6 × 105 M-1 s-1. 2,2-Dimethoxy-1-phenylpropane (18) is observed as a minor product. Laser flash photolysis experiments place an upper limit on methanol trapping of 5 at k 3 M-1 s-1 and do not provide any evidence for the formation of reactive intermediates other than 5. The use of two PTOC precursors containing different leaving groups to generate a common olefin cation radical enables one to utilize product analysis to probe for the intermediacy of other reactive intermediates. The ratio of 15:18 is dependent upon hydrogen atom donor concentration, but is independent of the PTOC precursor. These observations are consistent with the proposal that both products result from trapping of 5 that is formed via heterolysis of 3 and 4.

Hypercoordination of aluminum: Evidence for the implication of pentacoordinate complexes in the R2AlCl-promoted reduction of alkoxycarbonyl substrates

R2AlCl-promoted reductions of alkoxycarbonyl substrates with Bu3SnH were found to proceed diastereoselectively through the formation of pentacoordinate chelate-type complexes which have been characterized by 13C NMR spectr

Characteristic Reduction of Ketones by Bu3SnH-Bu4NX System

Various ketones were reduced cleanly by Bu3SnH-Bu4NX (X=halogen) combined systems.The reaction proceeds effectively under mild conditions.Chemoselective reduction was performed in bifunctional compounds, and marked diastereoselective reduction was noted for α-methoxy propiophenone.

Chelation of 2-substituted-1-lithoxides: Structural and energetic factors of relevance to synthetic organic chemistry

A number of lithium 2-(methylamino)-, 2-(dimethylamino)-, 2-methoxy-, and 2-(isopropylthio)-substituted-1-phenyl-1-propoxides were studied as models for asymmetric synthetic strategies for which lithium chelation between two electronegative atoms has frequently been invoked. The heats of formation of these alkoxides were determined by deprotonating the alcohols with lithium bis(trimethylsilyl)amide in a solution calorimeter. Aggregation numbers for the substituted alcohols and their corresponding lithium alkoxides were obtained with freezing point depression and vapor pressure osmometry in THF, benzene, and dioxane. In several cases, solution structures were obtained through 1H, 6Li, and 2D 6Li-1H NOE (HOESY) NMR spectroscopy. Solid-state structures of lithium (+)-N-methylpseudoephedrate and (-)-N-methylephedrate (+)-N-methylpseudoephedrate and (-)-N-methylephedrate (as the benzene solvate) were obtained by X-ray crystallography, and both were found to be present as tetramers in which the dimethylamino nitrogen atoms were coordinated to the lithium cations to form five-membered chelate rings. The lithium alkoxides were either tetramers or hexamers in nonpolar solvents; however, the alkoxides' solution structures were very complex in THF as evidenced by several 6Li resonances observed in the 6Li NMR spectra at low temperatures. Intramolecular lithium chelation was found to occur in each alkoxide in dioxane and benzene. The enthalpies of chelational stabilization were estimated by comparing their heats of deprotonation with those of nonchelatable 2-alkyl-substituted analogues. The stabilization enthalpies ranged from 5 to 11 kcal/mol per alkoxide molecule.