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Aldehydes alcohol synthesis from

C ( propyl) N phenylmtrone to N phenylmaleimide, 46, 96 semicarbazide hydrochloride to ami noacetone hydiochlonde, 46,1 tetraphenylcyclopentadienone to diphenyl acetylene, 46, 44 Alcohols, synthesis of equatorial, 47, 19 Aldehydes, aromatic, synthesis of, 47, 1 /3-chloro a,0 unsaturated, from ke tones and dimethylformamide-phosphorus oxy chloride, 46, 20 from alky 1 halides, 47, 97 from oxidation of alcohols with dimethyl sulfoxide, dicyclohexyl carbodumide, and pyndimum tnfluoroacetate, 47, 27 Alkylation, of 2 carbomethoxycyclo pentanone with benzyl chloride 45,7... [Pg.120]

Photocatalytic oxidation is a novel approach for the selective synthesis of aldehyde and acid from alcohol because the synthesis reaction can take place at mild conditions. These reactions are characterized by the transfer of light-induced charge carriers (i.e., photogenerated electron and hole pairs) to the electron donors and acceptors adsorbed on the semiconductor catalyst surface (1-4). Infrared (IR) spectroscopy is a useful technique for determining the dynamic behavior of adsorbed species and photogenerated electrons (5-7). [Pg.463]

The photocatalytic oxidation of alcohols constitutes a novel approach for the synthesis of aldehydes and acid from alcohols. Modification of Ti02 catalyst with Pt and Nafion could block the catalyst active sites for the oxidation of ethanol to CO2. Incorporation of Pt resulted in enhanced selectivity towards formate (HCOO ad)-Blocking of active sites by Nafion resulted in formation of significantly smaller amounts of intermediate species, CO2 and H2O, and accumulation of photogenerated electrons. The IR experimental teclmique has been extended to Attenuated Total Reflectance (ATR), enabling the study of liquid phase photocatalytic systems. [Pg.471]

It is a commercially important reaction as a step in the synthesis of nonanol, an important plasticizer alcohol. Other long chain alcohols, derived from product aldehydes by hydrogenation are used as the basis of soaps and... [Pg.8]

In two studies toward the total synthesis of natural products it could be shown that the a,jS-unsaturated esters derived from the vinylogous Mukaiyama aldol reactions can be further functionalized into advanced intermediates. The C1-C7 segment of oleandolide commences with the VMAR of aldehyde 68 derived from the Roche ester. The so-generated stereo-triad was protected as PMB ether and the ester 76 was reduced to the allylic alcohol. Sharpless asym-... [Pg.69]

The same basic strategy was applied to the synthesis of the smaller fragment benzyl ester 28 as well (Scheme 4). In this case, aldehyde 22 prepared from (S)-2-hydroxypentanoic acid [9] was allylated with ent-10 and tin(IV) chloride, and the resulting alcohol 23 was converted to epimer 24 via Mitsunobu inversion prior to phenylselenenyl-induced tetrahydrofuran formation. Reductive cleavage of the phenylselanyl group, hydrogenolysis of the benzyl ether, oxidation, carboxylate benzylation, and desilylation then furnished ester 28. [Pg.218]

The production of optically active cyanohydrins, with nitrile and alcohol functional groups that can each be readily derivatized, is an increasingly significant organic synthesis method. Hydroxynitrile lyase (HNL) enzymes have been shown to be very effective biocatalysts for the formation of these compounds from a variety of aldehyde and aliphatic ketone starting materials.Recent work has also expanded the application of HNLs to the asymmetric production of cyanohydrins from aromatic ketones. In particular, commercially available preparations of these enzymes have been utilized for high ee (5)-cyanohydrin synthesis from phenylacetones with a variety of different aromatic substitutions (Figure 8.1). [Pg.259]

Aldehyde 13, readily prepared by a four step synthesis from L-threonine,3a-i5 was treated with the known (Z)-7-methoxyallylboronate 1412a,c. This reaction, as with other reactions of pinacol allylboronates, was relatively slow and required 24-48 h at room temperature to reach completion. It was, however, extremely selective ana provided homoallyl alcohol 15 in 70% yield with greater than 95% diastereoselectivity. The stereochemistiy of this compound was quickly verified by conversion to 3 as shown in Figure 7.3a We now believe that this reaction proceeds by way of the Conforth-like transition state depicted in Figure 7, and not by way of a Felkin transition state as suggested in our original ublication, since a serious nonbonded interaction exists between the (Z)-methoxyl group and the C(3) substituents of 13 in the Felkin transition state. A... [Pg.245]

This new resin makes it possible to produce custom aldehydes and ketones from a wide range of carboxylic acids, including A-Boc-amino acids. No alcohol side product is observed, and the purity of the resulting aldehyde or ketone is so high that it may be used directly as a building block in parallel synthesis of chemical libraries. [Pg.222]

The high synthetic utility of alcohols 38 stems from the fact that terminal alkynes are among the most versatile functional groups for the further elaboration of a carbon skeleton. Asymmetric synthesis of alcohols 38 from aldehydes with the concurrent formation of the two stereogenic C atoms has been accomplished mainly by two methods. The first features synthesis of chiral nonracemic allenylmetal compounds from the corresponding chiral nonracemic propargyl alcohols and addition of the former to aldehydes [26] and the second method in-... [Pg.95]

Dehydrobromination of bromotrifluoropropene affords the more expensive trifluoropropyne [237], which was metallated in situ and trapped with an aldehyde in the TIT group s [238]synthesis of 2,6-dideoxy-6,6,6-trifluorosugars (Eq. 77). Allylic alcohols derived from adducts of this type have been transformed into trifluoromethyl lactones via [3,3] -Claisen rearrangements and subsequent iodolactonisation [239]. Relatively weak bases such as hydroxide anion can be used to perform the dehydrobromination and when the alkyne is generated in the presence of nucleophilic species, addition usually follows. Trifluoromethyl enol ethers were prepared (stereoselectively) in this way (Eq. 78) the key intermediate is presumably a transient vinyl carbanion which protonates before defluorination can occur [240]. Palladium(II)-catalysed alkenylation or aryla-tion then proceeds [241]. [Pg.162]

So, at the beginning of the 25-year period here commemorated, alcohols, glycols, aldehydes, and ketones, chlorinated hydrocarbons, esters, and ethers—all so vital in their direct uses or as chemical building blocks—were beginning to be produced by synthesis from hydrocarbons provided by the already well-grown petroleum and natural gas industries. Subsequent developments came in rapid succession, with remarkably little in-... [Pg.290]

A number of syntheses have been proposed, mainly from a-chlorosulfides and alcohols or from 0,0-acetals or 5,5-acetals. Many references on these methods are to be found in a paper dealing with a direct synthesis of 0,5-acetals from aldehydes [56],... [Pg.15]

The Corey-Kim Oxidation allows the synthesis of aldehydes and ketones from primary alcohols and secondary alcohols, respectively. [Pg.83]

A mixed oxide of ruthenium, copper, iron and alumnium has been developed as a catalyst for the synthesis of aldehydes and ketones from alcohols.258 Oxidation of chiral secondary 1,2-diols with 2,3-dichloro-5,6-dicyano-l,4-benzoquinone under ultrasound wave promotion leads to the selective oxidation of benzylic or allylic hydroxyl group. The configuration of the adjacent chiral centre is retained.259 The kinetics of oxidation of ethylbenzene in the presence of acetic anhydride have been studied.260... [Pg.115]

C-Sucrose. A key step in a synthesis of this saccharide involves as the first step the coupling of a vinyl iodide with an aldehyde mediated by CrCl2 and a trace of NiCl2 (14, 97-98). Thus coupling of the vinyl iodide 1 with the aldehyde 2, derived from D-arabinose, provides an allylic alcohol, which on Mitsunobu inversion provides the threo alcohol 3 as the major product. This is converted to C-sucrose... [Pg.96]

Halides are second only to carboxylic acids in their versatility in organic synthesis. Functional group transformations into alkenes, alkynes, amines, aldehydes, alcohols, ethers, hydrocarbons, ketones and other groups may be performed with ease in high yield. However, the major synthetic importance of halides arises from the ease by which compounds that contain this functionality may be used in carbon-carbon bond-forming reactions and in the preparation of heterocyclic compounds. [Pg.710]

Cook and co-workers have described a Pd-catalyzed domino reaction for the preparation of the quinuclidine subunit common to a variety of alkaloids, e.g., 146 to 147 <07OL1469>. In a separate report from the same group, enantiospecific total synthesis of 6-epi-vellosimine 148 proceeded with judicious use of the Corey-Kim reagent (NCS/N S/CH Ch EtsN) for mild access to the delicate axial aldehyde of 148 from the corresponding alcohol <07OL295>. [Pg.144]

Chiral homoallylic alcohols, The glycol 1 has been used as the chiral matrbt in an enantioselective synthesis of homoallylic alcohols (4) from aldehydes and allyl-boranes (equation I). [Pg.488]


See other pages where Aldehydes alcohol synthesis from is mentioned: [Pg.103]    [Pg.244]    [Pg.230]    [Pg.311]    [Pg.212]    [Pg.293]    [Pg.419]    [Pg.157]    [Pg.107]    [Pg.145]    [Pg.7]    [Pg.34]    [Pg.294]    [Pg.9]    [Pg.128]    [Pg.324]    [Pg.124]    [Pg.401]    [Pg.815]    [Pg.1097]    [Pg.524]    [Pg.146]    [Pg.345]    [Pg.179]    [Pg.278]    [Pg.410]   
See also in sourсe #XX -- [ Pg.300 ]




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