75088-70-9

Upstream product

• 1864-94-4 phenyl formate 
• 10294-34-5 boron trichloride 
• 122-79-2 Phenyl acetate 
• 101-02-0 triphenyl phosphite 
• 150-19-6 O-methylresorcine 
• 946-80-5 (benzyloxy)benzene 
• 40515-89-7 2-phenethoxybenzene 
• 108-95-2 phenol 
• 100-66-3 methoxybenzene 
• 1095-03-0 triphenylborane 

Downstream Products

• 1095-03-0 triphenylborane 
• 10294-34-5 boron trichloride 
• 850446-94-5 1,3-bis(trimethylsilyl)-2-phenoxy-1,3,2-diazabora-[3]-ferrocenophane 

Relevant academic research and scientific papers

BBr3-Assisted Preparation of Aromatic Alkyl Bromides from Lignin and Lignin Model Compounds

For the first time, BBr3-assisted nucleophilic substitution was applied to a variety of β-O-4 and α-O-4 model compounds for the highly effective cleavage of different C-O bonds, including C-Oα-OH, Cβ-O/Cα-O and CMe-O bonds (99% conversion for most cases). Without any pretreatment, the substitution proceeds at room temperature in the absence of any catalyst, or additive, selectively affording phenols and important organic synthesis reagents, aromatic alkyl bromides, in high to excellent yields (up to 98%). Preliminary studies also highlight the prospect of this method for the effective cleavage of different types of C-O bonds in real lignin. A total 14 wt % yield of aromatic alkyl bromide, 4-(1,2-dibromo-3-hydroxypropyl)benzene-1,2-diol (10), has been obtained from an extracted lignin through this method.

Formylation of activated arenes by phenyl formate: Implications for the mechanism of the Fries rearrangement of aryl formates

We present an NMR and DFT investigation of the reaction of phenyl formate with 3-methoxyphenol and 3,5-dimethoxyphenol with excess BCl3. The products obtained (3-methoxy- and 3,5-dimethoxy-salicylaldehyde, respectively) are the same as those resulting from the Fries rearrangement of 3-methoxy- and 3,5-dimethoxy-phenyl formate. These results represent a novel regioselective synthetic route to aromatic aldehydes, using phenyl formate as a source of formylating agent. They also unambiguously prove that the Fries rearrangement of aryl formates (that we recently investigated in J. Org. Chem. 71, 9331-9340, 2006) is intermolecular: the intermediate formyl chloride is released in situ and, in turn, it formylates the intermediate dichloroborate ester of 3-methoxy- and 3,5-dimethoxy-phenol in a second independent step. The -BCl2 moiety bound to the aryl oxygen of the substituted phenol interacts with the formyl chloride strongly favouring the ortho substitution. Copyright

Fries rearrangement of aryl formates: A mechanistic study by means of 1H, 2H, and 11B NMR spectroscopy and DFT calculations

(Figure Presented) 1H, 2H, and 11B NMR spectroscopy has been used to study the mechanism of the Fries rearrangement of aryl formates promoted by boron trichloride by monitoring both the substrate and the Lewis acid. DFT calculations were employed to investigate the energetics of several reaction paths and to calculate NMR chemical shifts of key intermediates and products. After the formation of a 1:1 substrate - Lewis acid adduct, the rearrangement proceeds in two steps, beginning with the cleavage of the ester bond and the release of formyl chloride in situ, which, in turn, acts as a formylating agent, introducing an aldehydic functionality into the aromatic ring. The high regioselectivity (only the ortho product is obtained) is also accounted for by the proposed intermolecular, Lewis acid-assisted mechanism.