Various types of aromatic aldehydes were efficiently converted to their corresponding 1,3-dioxanes and 1,3-dioxolane with 1,3-propanediol and ethylene glycol, respectively, in the presence of catalytic amount of ZrO(OTf)2 in acetonitrile at room temperature. The catalyst can be reused several times without loss of its catalytic activity. Very short reaction times, selective acetalization of aromatic
acyclic acetals to the corresponding hydroxyalkyl carboxylic esters and simple esters, respectively. 2-Iodoxybenzoic acid (IBX) in the presence of tetraethylammonium bromide was employed for the reaction in aqueous media. The salient features of the protocol include short reaction time, environmentally benign reagents and solvent, and moderate to high yields. o-iodoxybenzoic acid - acetals - oxidations
CYCLIC ACETALS OF 2-PHENYL-C3-C5-ALKANALS AND STEREOISOMERS THEREOF FOR USE AS AROMA CHEMICALS
申请人:BASF SE
公开号:EP3553055A1
公开(公告)日:2019-10-16
The present invention relates to the use of cyclic acetals of 2-phenyl-C3-C5-alkanals of the formula (I)
where the variables are as defined in the claims or the description, or of stereoisomers or of stereoisomer mixtures thereof or of double bond isomers of specific compounds of the formula (I) as aroma chemicals, to the use thereof for modifying the scent character of a fragranced composition; to an aroma chemical containing said cyclic acetals or a stereoisomer or a mixture of stereoisomers thereof; and to a method of preparing a fragranced composition or for modifying the scent character of a fragranced composition. The invention further relates to specific cyclic acetals of the formula (I), to stereoisomers thereof, to stereoisomer mixtures thereof, to double bond isomers of specific compounds of the formula (I), and to a method for the preparation of cyclic acetals of the formula (I).
Facile oxidative hydrolysis of acetals to esters using hypervalent iodine(III)/LiBr combination in water
作者:Waraporn Panchan、Supanimit Chiampanichayakul、Deanna L. Snyder、Siriporn Yodbuntung、Manat Pohmakotr、Vichai Reutrakul、Thaworn Jaipetch、Chutima Kuhakarn
DOI:10.1016/j.tet.2010.01.098
日期:2010.4
The combination of (diacetoxy)iodobenzene (Phl(OAc)(2), DIB) and lithium bromide (LiBr) efficiently oxidized cyclic and acyclic acetals to the corresponding hydroxyalkyl carboxylic esters and simple esters in good to excellent yields The merits of this reaction are that it employs commercially available and non-explosive hypervalent iodine(III) reagent, water as the solvent, a short reaction tune, and mild reaction conditions (C) 2010 Elsevier Ltd All rights reserved