𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Improved preparation of angelate esters

✍ Scribed by Benoît Hartmann; Alice M. Kanazawa; Jean-Pierre Deprés; Andrew E. Greene

Book ID
104225826
Publisher
Elsevier Science
Year
1991
Tongue
French
Weight
221 KB
Volume
32
Category
Article
ISSN
0040-4039

No coin nor oath required. For personal study only.

✦ Synopsis

A new procedure has been developed for the efficient preparation of angelate esters from alcohols. The alcohol is treated in dry toluene at 70-80 =C for 19-36 h with a mixed anhydride prepared from angelic acid and 2,4,6-tdchlorobenzoyl chloride. In the absence of base, no tiglate ester is produced.

We recently required an efficient esterification procedure for the preparation of the angelate ester homogynolide-A (2) from the corresponding alcohol (1, eq 1).1 In that angelates are common

O CH3

CHz 1 2 in nature, it was particularly surprising to discover that a methodological lacuna existed for this seemingly straightforward type of conversion.

To effect this esterification most frequently the alcohol has been treated with angeloyl chloride (e.g., eq 2).2 This procedure, however, usually affords the desired angelate in only poor to modest ,,~CO2CH3 CH3x~COCI CHs .

📜 SIMILAR VOLUMES

Improved preparation of aliphatic propyn
Improved preparation of aliphatic propynoic esters
✍ L. Balas; B. Jousseaume; B. Langwost 📂 Article 📅 1989 🏛 Elsevier Science 🌐 French ⚖ 120 KB

Alcohol Yield (%)(a) l-octanol 68 1.4-Butanediol 66 buyI alcohol 52 a-Methylbenzyl alcohol 76 3J-Hexadien-l-01 72 z-plopen-l-01 75 3-Phenyl-Zpropen-l-o1 71 t-Butanol 0 (18) I-Methyl-1-phenyl ethanol 0 1X-LNMR (CC4, (ppmi) 0.8S1.8 (m,15H) :2.8~(s,lH) ;4.12 (t,2H) 1.65-1.9 (m,4H) ; 2.82 (s,2H) ; 4.15