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  • Di(hydroperoxy)adamantane adducts: synthesis, characterization and application as oxidizers for the direct esterification of aldehydes
Title: Di(hydroperoxy)adamantane adducts: synthesis, characterization and application as oxidizers for the direct esterification of aldehydes
The di(hydroperoxy)adamantane adducts of water (1) and phosphine oxides p -Tol 3 PO·(HOO) 2 C(C 9 H 14 ) (2), o -Tol 3 PO·(HOO) 2 C(C 9 H 14 ) (3), and Cy 3 PO·(HOO) 2 C(C 9 H 14 ) (4), as well as a CH 2 Cl 2 adduct of a phosphole oxide dimer (8), have been created and investigated by multinuclear NMR spectroscopy, and by Raman and IR spectroscopy. The single crystal X-ray structures for 1–4 and 8 are reported. The IR and 31 P NMR data are in accordance with strong hydrogen bonding of the di(hydroperoxy)adamantane adducts. The Raman ν (O–O) stretching bands of 1–4 prove that the peroxo groups are present in the solids. Selected di(hydroperoxy)alkane adducts, in combination with AlCl 3 as catalyst, have been applied for the direct oxidative esterification of n -nonyl aldehyde, benzaldehyde, p -methylbenzaldehyde, p -bromobenzaldehyde, and o -hydroxybenzaldehyde to the corresponding methyl esters. The esterification takes place in an inert atmosphere, under anhydrous and oxygen-free conditions, within a time frame of 45 minutes to 5 hours at room temperature. Hereby, two oxygen atoms per adduct assembly are active with respect to the quantitative transformation of the aldehyde into the ester.  more » « less
Award ID(s):
1900100
PAR ID:
10339951
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Dalton Transactions
Volume:
50
Issue:
42
ISSN:
1477-9226
Page Range / eLocation ID:
15296 to 15309
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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