𝔖 Bobbio Scriptorium
✦   LIBER   ✦

The reaction of phenol with formaldehyde: II. The ratio of ortho- and para-hydroxymethylphenol in the base-catalyzed hydroxymethylation of phenol.

✍ Scribed by H. G. Peer

Publisher
Elsevier Science
Year
2010
Tongue
English
Weight
531 KB
Volume
78
Category
Article
ISSN
0165-0513

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

A kinetic study of the first step in the reaction of phenol and formaldehyde, the formation of ortho‐ and para‐hydroxymethylphenol, is described.

It is found that when using NaOH or KOH as a catalyst under weakly alkaline conditions (pH = 8.5‐10.5) at 30° C, the para‐position in the phenolic nucleus is nearly twice as reactive as the ortho‐position (the ortho/para ratio being 1.10). Interesting effects are observed in more strongly alkaline media (pH = 10.5‐13.5), inter alia a sharp decrease in the ortho/para ratio with increasing value of pH.

When other hydroxides are used, an increasing value of the ortho/para ratio is found with the hydroxides of K, Na, Li, Ba, Sr, Ca and Mg, respectively. Probably chelate formation occurs in the transition state for ortho substitution.

📜 SIMILAR VOLUMES

The reaction of phenol with formaldehyde
The reaction of phenol with formaldehyde. III. selective hydroxymethylation of phenols at the ortho-position
✍ H. G. Peer 📂 Article 📅 2010 🏛 Elsevier Science 🌐 English ⚖ 493 KB

## Abstract The effect of chelating substances on the orientation of hydroxymethyl groups in the reaction of phenol with formaldehyde is described. It is found that when using hydroxides of the transition metals, Cu, Cr, Mn, Ni and Co, in aequous solution at pH = 4‐5, hydroxymethylation occurs mai

On the para/ortho product ratio of pheno
On the para/ortho product ratio of phenol and anisole hydroxylation over titanium silicalite-1
✍ Dr. rer. nat. Sabina Vetter; Dr. rer. nat. Günter Schulz-Ekloff; Dip.-Chem. Korn 📂 Article 📅 1994 🏛 John Wiley and Sons 🌐 English ⚖ 519 KB

Titanium silicalite-1 samples of different particle size are synthesised and characterised by X-ray diffraction (XRD), photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), Raman and infrared spectroscopy. Size histograms are taken from transmission electron micrographs. Temporal