59848-69-0

Usage

InChI:InChI=1/C10H18O/c1-8(2)6-10-7-9(3)4-5-11-10/h4,8,10H,5-7H2,1-3H3

Upstream product

• 763-32-6 2-methyl-1-buten-4-ol 
• 590-86-3 isovaleraldehyde 
• 58303-58-5 2-Isobutyl-4,4-dimethyl-1,3-dioxane 
• 99806-26-5 3-bromo-4-hydroxy-2-methyl-1-butene 
• 7437-61-8 2-methyl-3,4-epoxy-1-butene 
• 108-10-1 4-methyl-2-pentanone 
• 23007-34-3 6-hydroxy-2,6-dimethyl-oct-7-en-4-one 
• 352-66-9 3-methylbutyroyl fluoride 
• 136123-55-2 isovaleryl fluorosulfonate 
• 78-79-5 isoprene 
• 50-00-0 formaldehyd 
• 115-11-7 isobutene 
• 101004-57-3 5-bromo-4-chloro-2-isobutyl-4-methyltetrahydropyran 
• 62032-60-4 2,6-Dimethyl-1-octen-3,5-diol 

Relevant academic research and scientific papers

Heteropoly acid catalysts in Prins cyclization for the synthesis of Florol

H3PW12O40 heteropoly acid supported on SiO2 and its bulk acidic cesium salt Cs2.5H0.5PW12O40 are demonstrated to be highly active and recyclable solid catalysts for Pr

PRODUCTION OF 2-SUBSTITUTED 4-METHYL-TETRAHYDROPYRANS FROM STARTING MATERIALS CONTAINING 2-ALKYL-4,4-DIMETHYL-1,3-DIOXANES

The invention relates to a method for producing 2-substituted 4-methyltetrahydropyrans of general formula (I) from starting materials containing at least one 2-substituted 4,4-dimethyl-1,3-dioxane of general formula (II).

Contribution to elucidation of the mechanism of preparation of 2-isobutyl-4-methyltetrahydro-2H-pyran-4-ol

The effects of catalyst type (sulfuric acid, Amberlyst 15, p-toluenesulfonic acid, and p-dodecylbenzenesulfonic acid) and of addition of water on the preparation of 2-isobutyl-4-methyltetrahydro-2H-pyran-4-ol by Prins cyclization were studied. It was discovered that in the absence of added water the amphiphilic character of the acid had the main effect and that organic acids were unsuitable for preparation of this compound. From the perspective of the ratio of the amount of the desired product to that of dihydropyrans, after addition of water the results obtained by use of p-toluenesulfonic acid (ratio 3.5, selectivity 67 %) were comparable with those obtained by use of sulfuric acid and were better than those obtained by use of Amberlyst 15 (ratio 2.3, selectivity 68 %). A detailed study of the mechanism confirmed that addition of water to the double bonds of dihydropyrans does not occur.

Process for the preparation of dihydropyrans

The invention provides a process for the preparation of 5,6-dihydro-2H-pyran derivatives, wherein an aldehyde of formula I: STR1 wherein R1 represents an alkyl, cycloalkyl, aralkyl, alkaryl or aryl group having at most 15 carbon atoms and a diene of formula II: STR2 wherein R2 and R3 represents a hydrogen atom or an alkyl group having 1-6 carbon atoms are reacted in a Diels-Alder-type reaction under the influence of an inorganic Lewis acid catalyst, producing a compound of formula III wherein R1 -R3 have the meaning given above. STR3 Preferably R1 represents a 1-6 carbon atom alkyl group, a phenyl group or an o-, m- or p-tolyl group. Isoprene or 2-methyl-1,3-pentadiene is preferably used as the diene. The preferred catalyst is AlCl3 or SnCl4 and an organic nitro compound may be used as the co-catalyst.

ACYLATION OF 1,3-ALKADIENES BY ACYL FLUOROSULFONATES. STEREOSPECIFIC SYNTHESIS OF E AND Z ISOMERS OF CONJUGATED DIENONES

Acyl fluorosulfonates generated from acyl fluorides and SO3 permits acylation of butadiene and isoprene to give triconjugated dienones.This reaction proceeds stereospecifically and leads to E isomers of the corresponding dienones in the case of butadiene and Z isomers in the case of isoprene.

1,2-ELIMINATION OF ALCOHOL FROM HOMOALLYL ETHERS UNDER THE INFLUENCE OF MIXED METAL BASES

Lithium diisopropylamide in the presence of catalytic amounts of potassium tert-butoxide smoothly converts homoallyl or homobenzyl type ethers to dienes (e.g., 1, 3, 5, 26) or styrenes (2). γ,δ-Unsaturated acetals give 1,3-dienyl ethers (e.g., 4) and 4-alkylidenetetrahydropyrans or dihydropyrans produce a variety of dienols (e.g., 6 - 17, 20 - 22). - If there is a choice, the new double bond is formed with high trans-selectivity while the configuration of existing double bonds is retained. - The elimination mode is syn-periplanar and concerted, though E1cb like.

REACTIONS ON A SURFACE. 1. CONDENSATION OF 3-METHYL-3-BUTEN-1-OL WITH CARBONYL COMPOUNDS ON SiO2 AND Al2O3

3-Methyl-3-buten-1-ol reacts with various aldehydes and ketones on silica gel and Al2O3 surfaces in the absence of solvents and conventional catalysts for this reaction to form derivatives of di- and tetrahydropyrans.

REGIOSPECIFIC SYNTHESIS OF 2-SUBSTITUTED 4-METHYL-3,6-DIHYDRO-2H-PYRANS

The chloroalkylation of 3-halo-2-methyl-1-buten-4-ols was used to synthesize 4,5-dihalo-4-methyl-2-substituted tetrahydropyrans, which were converted regiospecifically to 3,6-dihydropyrans by reaction with magnesium.A similar reaction with zinc dust gave mixtures of 3,6- and 5,6-dihydropyrans.

DIMETHYLALUMINUM CHLORIDE CATALYZED ENE REACTIONS OF ALDEHYDES.

Dimethylaluminum chloride, which is a mild Lewis acid and a proton scavenger, catalyzes the ene reactions of aliphatic and aromatic aldehydes with alkenes containing a disubstituted vinylic carbon. Proton-initiated rearrangements do not occur, since the alcohol-Lewis acid complex formed in the ene reaction reacts rapidly to give methane and a nonacidic aluminum alkoxide. Formaldehyde and excess Me//2AlCl give good yields of ene adducts with all types of alkenes. With 1 equiv of Me//2AlCl, formaldehyde and mono- and 1,2-disubstituted alkenes give gamma -chloro alcohols resulting from cis addition of chlorine and hydroxymethyl groups to the double bond. This work is pertinent to the synthesis of alcohols.