29539-18-2

Upstream product

• 67-56-1 methanol 
• 119367-66-7 C₂₂H₂₂N₂O₃S 
• 5773-56-8 1,2-Diphenylethanol 
• 119391-24-1 C₂₂H₂₁N₂O₃S^(1-)*Li⁽¹⁺⁾ 
• 119391-25-2 C₂₂H₂₁N₂O₃S^(1-)*Na⁽¹⁺⁾ 
• 38453-85-9 2-[2-(hydroxymethyl)phenyl]-1-phenylethanol 
• 50-00-0 formaldehyd 
• 100-52-7 benzaldehyde 
• 100-44-7 benzyl chloride 
• 496-14-0 1,3-dihydroisobenzofuran 
• 87-41-2 2-benzofuran-1(3H)-one 
• 119367-90-7 2-<(Benzyloxy)methyl>benzyl alcohol 
• 119367-65-6 2-<(Benzyloxy)methyl>benzaldehyde 
• 119367-89-4 2-<(Benzyloxy)methyl>benzoic acid 

Downstream Products

• 2881-31-4 2-(2-oxo-2-phenylethyl)benzoic acid 
• 2674-44-4 3-phenyl-isochroman-1-one 
• 153396-48-6 3,4-dihydro-3-phenyl-H-2-benzopyran-1-ol 

Relevant academic research and scientific papers

Cyclic acetals as precursors of substituted isochromans and naphthoxepines

The reaction of 6,8-dioxabenzocycloheptenes 3 or 8,10-dioxacycloocta[de]naphthalenes 5 [easily prepared from the dibenzylic diols 1 and 4, respectively, and a carbonyl compound] with an excess of lithium and a catalytic amount of DTBB (2.5 mol %) in THF a

A case of pictet-spengler revisited: Application to the synthesis of dihydroisocoumarins

The reaction of Pictet-Spengler was revisited, and its modified conditions were applied to develop a general methodology toward the synthesis of dihydroisocoumarins containing a no-electron rich aromatic ring.

Improved procedure for 3,4-dihydro-1H-2-benzopyran ring closure. A general access to 3-substituted isochromanes

A general method for the ring closure of 1-substituted 2-(- hydroxymethyl)-phenylethanols to 3-substituted isochromanes using p-TsOH supported on silica gel is reported.

Electron-transfer-induced reductive cleavage of phthalans: Reactivity and synthetic applications

The behavior of phthalan (1a) was investigated under conditions of electron transfer from alkali metals in aprotic solvents. Reaction with lithium in the presence of a catalytic amount of naphthalene in THF led to the reductive cleavage of an arylmethyl carbon-oxygen bond, with formation of a stable dilithium compound. Trapping of this intermediate with several electrophiles (alkyl halides, carbonyl derivatives, CO2) was successful. The extension of this procedure to several substituted phthalans (1b-i) was investigated, and the regiochemistry as well as the synthetic usefulness of these reactions are discussed.

1,2-Di(lithiomethyl)benzene from Phthalan: Sequential Introduction of Two Different Electrophiles

The reaction of phthalan (1) with an excess of lithium powder and a catalytic amount of DTBB (2.5 mol percent) in THF at 20 deg C followed by treatment with electrophiles (D2O, CO2 and carbonyl compounds) at -78 deg C leads, after hydrolysis, to the corresponding functionalised benzylic alcohols 3a-g.When the lithiation reaction is continued, after the reaction with the first electrophile, and a second electrophile (H2O, D2O and carbonyl compounds) is added, the corresponding disubstituted compounds 6a-q are prepared.Diols 3c-g and 6h,i,l,n and hydroxyacids 6a,c,f,k are easily dehydrated to the corresponding cyclic ethers (7c-f, 8h,i,l,n) or lactones (9a,c,f,k) respectively.Finally, alcohols 6b,d,e give, after acid treatment, the Friedel-Crafts type benzocyclopentenes 10b,d,e.

Reductive electrophilic substitution of phthalans and ring expansion to isochroman derivatives

Reductive cleavage of phthalan, 1a, with Li metal in the presence of a catalytic amount of naphthalene leads to the formation of a stable aromatic dilithium compound. The adducts of the latter with CO2, aldehydes or ketones undergo ring closure to isochroman derivatives, leading to ring expansion of the original heterocycle. The reductive electrophilic substitution procedure was successfully extended to the substituted phthalans 1b and 1c, to afford the corresponding isochroman-3-ones in satisfactory yields.

THE REACTION OF BENZYLIC ALCOHOLS WITH CHLOROTRIMETHYLSILANE/DIMETHYL SULPHOXIDE

With catalytic amounts of chlorotrimethylsilane/dimethyl sulphoxide (CTMSO/DMSO) in acetonitrile benzylic alcohols have been found to give high yields of styrenes.By using stoicheiometric amounts of reagents, different reaction pathways are observed: an elimination-addition sequence occurs with secondary and tertiary alcohols affording vicinal dichloro derivatives, β-chloro thioethers and allyl chlorides, whereas a nucleophilic substitution to the corresponding monochlorides occurs starting from primary and sterically hindered substrates.

Intramolecular Generation of Oxonium Ylides from Functionalized Arylcarbenes

Arylcarbenes carrying alkoxyalkyl groups in the ortho position have been generated by flash pyrolysis and photolysis of appropriate tosylhydrazone sodium salts.In the gas phase and in a aprotic solvents, interaction of the carbenes with the lone electron pairs of oxygen competes efficiently with insertion into C-H bonds.Both five- and six-membered cyclic oxonium ylides have been generated.The ylides 23, 37, 61b, and 74 undergo 1,2 shifts of benzyl groups with ease, even if ring contraction to highly strained benzocyclobutenes is involved (23, 74).The oxonium ylides37 and 61b strongly prefer the nonconcerted Stevens rearrangement to the sigmatropic Sommelet rearrangement, in contrast to analogous ammonium ylides.Alkyl shifts occur to a very minor extent, if at all.Evidence is presented that alcohols intercept both the carbenes and the oxonium ylides.Protonation of the ylides leads to cyclic oxonium ions, which undergo nucleophilic cleavage of the C-O bonds.Acid catalyzed decomposition of the appropriate diazo compounds gives rise to six-membered, but not to five-membered, cyclic oxonium ions, thus confirming the different intramolecular reactivities of arylcarbenes and benzyl cations.The efficiency of carbene interception increases with increasing acidity of the medium, suggesting nucleophilic behavior (protonation) of the arylcarbenes.