Butyl acetate aldehyde

In another approach, a glucose-derived titanium enolate is used in order to accomplish stereoselective aldol additions. Again the chiral information lies in the metallic portion of the enolate. Thus, the lithiated /m-butyl acetate is transmetalated with chloro(cyclopentadienyl)bis(l,2 5,6-di-0-isopropylidene- -D-glucofuranos-3-0-yl)titanium (see Section I.3.4.2.2.I. and 1.3.4.2.2.2.). The titanium enolate 5 is reacted in situ with aldehydes to provide, after hydrolysis, /i-hydroxy-carboxylic acids with 90 95% ee and the chiral auxiliary reagent can be recovered76. 

The addition of lithium enolates to 2-alkoxyaldehydes occurs either in a completely non-stereoselective manner, or with moderate selectivity in favor of the product predicted by the Cram-Felkin-Anh model28 ( nonchelation control 3, see reference 28 for a survey of this type of addition to racemic aldehydes). Thus, a 1 1 mixture of the diastereomeric adducts results from the reaction of lithiated tert-butyl acetate and 2-benzyloxypropanal4,28. 

In the presence of a strong base, the ot carbon of a carboxylic ester can condense with the carbonyl carbon of an aldehyde or ketone to give a P-hydroxy ester, which may or may not be dehydrated to the a,P-unsaturated ester. This reaction is sometimes called the Claisen reaction,an unfortunate usage since that name is more firmly connected to 10-118. In a modem example of how the reaction is used, addition of tert-butyl acetate to LDA in hexane at -78°C gives the lithium salt of ferf-butyl acetate, " (12-21) an enolate anion. Subsequent reaction a ketone provides a simple rapid alternative to the Reformatsky reaction (16-31) as a means of preparing P-hydroxy erf-butyl esters. It is also possible for the a carbon of an aldehyde or ketone to add to the carbonyl carbon of a carboxylic ester, but this is a different reaction (10-119) involving nucleophilic substitution and not addition to a C=0 bond. It can, however, be a side reaction if the aldehyde or ketone has an a hydrogen. 

Covalently bonded chiral auxiliaries readily induce high stereoselectivity for propionate enolates, while the case of acetate enolates has proved to be difficult. Alkylation of carbonyl compound with a novel cyclopentadienyl titanium carbohydrate complex has been found to give high stereoselectivity,44 and a variety of ft-hydroxyl carboxylic acids are accessible with 90-95% optical yields. This compound was also tested in enantioselective aldol reactions. Transmetalation of the relatively stable lithium enolate of t-butyl acetate with chloro(cyclopentadienyl)-bis(l,2 5,6-di-<9-isopropylidene-a-D-glucofuranose-3-0-yl)titanate provided the titanium enolate 66. Reaction of 66 with aldehydes gave -hydroxy esters in high ee (Scheme 3-23). 

This procedure illustrates the use of lithio esters for the preparation of /3-hydroxy esters. Isopropyl and /-butyl /3-hydroxy-/8,/3-diphenylpropionate may be prepared in approximately 80% yields by using isopropyl or /-butyl acetates in place of ethyl acetate.2 This procedure is generally more convenient than the Reformatsky reaction for the preparation of such esters. Under similar conditions ethyl acetate may conveniently be condensed with various aldehydes or ketones to give the corresponding /8-hydroxy esters.4... 

Prior to the actual metathesis event, coupling of 13 and 28 via an ester linkage was required (Scheme 2.3). Two methods were employed in this connection. The first involved the aforementioned two-carbon expansion of aldehyde 28. Thus, condensation of 28 with Rathke anion (lithiated tert-butyl acetate) generated a mixture of dia-stereomeric alcohols the major product was shown to have the requisite 3S configuration. TBS protection of ester 29 and subsequent ester hydrolysis generated the desired add, 31, which could be further esterified with alcohol 13 in 78 % yield. 

The synthesis of (-t-)-benzoylselenopederic acid (569) (477) (Scheme 71), the left-hand half of pederin (147), began with (-f-)-3-keto imide 570, which was subjected to the recently developed syn-directing Zn(BH4)2 reduction (482) to give 5yn-a-methyl-3-hydroxy acid derivative 571. Imide 571, after protection of the hydroxyl group as the THP ether, was reduced with DIBAH, and the resulting aldehyde was treated with lithium enolate of tm-butyl acetate to give the p-... 

Acetic Acid, Cupric Salt Acetic Acid, Dimethylamide Acetic Acid, Ethyl Ester Acetic Acid, Isobutyl Ester Acetic Acid, Isopropyl Ester Acetic Acid, Methyl Ester Acetic Acid, Nickel (II) Salt Acetic Acid, Propyl Ester Acetic Acid, Sec-Butyl Ester Acetic Acid, Zinc Salt Acetic Aldehyde Acetic Anhydride Acetic Ester Acetic Ether... 

Enantioselective aldol reaction -hydroxy esters.2 The lithium enolate 4 of t-butyl acetate reacts with an aldehyde in the presence of 2 to form P-hydroxy esters 6 in 90-96% ee. 

Reaction of the complex 1 with the lithium enolate of f-butyl acetate provides a complex 4, which reacts with aldehydes to form 3-hydroxy esters (5) in 90-96% ee.2... 

Butter Starter Distillate, 394 Butyl Acetate, 462, 649 -Butyl Acetate, 462 Butyl Alcohol, 462, 649, (S 1)62 Butyl Aldehyde, 462 Butylated Hydroxyanisole, 44 Butylated Hydroxymethylphenol, 51 Butylated Hydroxytoluene, 45 Butyl Butyrate, 462, 650 n-Butyl -Butyrate, 462 Butyl Butyryllactate, 462, 609 2-sec-Butyl Cyclohexanone, (S3)66, 97... 

Examples are given of common operations such as absorption of ammonia to make fertilizers and of carbon dioxide to make soda ash. Also of recovery of phosphine from offgases of phosphorous plants recovery of HF oxidation, halogenation, and hydrogenation of various organics hydration of olefins to alcohols oxo reaction for higher aldehydes and alcohols ozonolysis of oleic acid absorption of carbon monoxide to make sodium formate alkylation of acetic acid with isobutylene to make fert-butyl acetate, absorption of olefins to make various products HCl and HBr plus higher alcohols to make alkyl halides and so on. 

Acetylation of alcohols and phenols by ketene has limited use. Unless apparatus for the preparation of ketene is readily available, less troublesome methods can usually be found. Worthy of mention, however, are the acetylations of lactic esters in 94-98% yields and of tertiary alcohols and phenols in 89-96% yields.Catalysts are necessary even to convert a high percentage of n-butyl alcohol to n-butyl acetate. Sulfuric and p-toluenesulfonic acids are commonly used. Certain aldehydes and ketones are attacked by ketene. Acetates of enol forms of ketones may be made in this way. ° Under certain conditions / -lactones are formed (cf. method 327),... 

Ester Content (as Ethyl Acetate) — min 85 0 max 88,0%, It shall be detd in accordance with ASTM D1617-69, described in Annual Book of ASTM Standards, Part 20(1972), 736-39 Note 1. The method described in ASTM Dl6l7— 69 applies not only to EtAcet, but also to other esters, such as N-butyl acetate, isopropyl acetate, acetate ester of ethylene glycol monoethyl ether, sec-butyl acetate, amyl acetate, dibutyl phthalate and iso butyl acetate Note 2 Org chlorides, nitriles and amides interfere. Ketones and aldehydes interfere only slightly with this procedure... 

An important development is the use of D-glucose-derived alkoxy ligands on titanium in cyciopentadi-enyldi(alkoxy)titanium enolates, which undergo efficient enantioselective aldol reactions with aldehydes. The chiral titanium reagent (30), prepared from reaction of cyclopentadienyltitanium trichloride with two equivalents of (l,2 5,6)-di-0-isopropylidene-a-D-glucofuranose, can be used to transmetal late the lithium enolate of t-butyl acetate in ether solution (equation 10). The titanium enolate generated is then... 

Danishefsky s first macrolactonization [142d] to 5a was carried out using 568 (Scheme 81), which was prepared starting from 562. The Cl-ClO ester 562 was synthesized from acetal 561 (Scheme 79). After hydrolysis of the acetal 561, the resulting aldehyde was subjected to aldol reaction with t-butyl acetate to give a-and p-alcohols in a 2 1 ratio. The desired a-alcohol was further converted to TBS ester 562 in standard fashion. As shown in Scheme 81, Suzuki coupling of 562 and 565 followed by hydrolysis of the ester afforded hydroxy carboxylic... 

The actual umpolung reaction that allows a ketene dithioacetal to function as if it had an electrophilic carbon a to a carbonyl is achieved by conjugate addition of nucleophiles to the ketene dithioacetal, followed by hydrolysis. Both sulfide and sulfoxide ketene derivatives can be used. Conjugate addition of an ester enol-ate derived from ferf-butyl acetate (secs. 9.2, 9.4.B, 9.7.A) to the ketene dithioacetal [CH2=C(SOMe)2] gave the stable dithioacetal anion (382). Conversion of the dithioacetal to the bis(sulfoxide) enhanced the ability of that species to function as a Michael acceptor. Subsequent transformation of 382 gave the aldehyde-ester (383).370... 

Volatile analysis of olive oil has been well reported (1, 3). Environmental factors as well as cultivar are a major influence on volatile production in the oil (1). In order to study the effect of cultivar we have used callus cultures which have previously proved to possess an acyl composition compatable with the developing olive fruit (2). Table 1 shows some of the major volatile constituents of the callus cultures which have also been identified in virgin olive oil (3). They included aldehydes, alcohols, esters, hydrocarbons and ketones. The presence of aldehydes, such as hexanal and trans-2-hexenal, as well as their alcohol derivatives (commonly known as the leaf alcohols) were indicative of an active LOX pathway and alcohol dehydrogenase activity. The aromatic properties of the oil are attributed to just a few of these constitutents. Hexanal, trans-l-hcxcnsLi, 3-methylbutan-l-ol, nonanal and trans-2-hexen-l-o are particularly important volatile components of olive oil (1). Morales et al (3) have also found that butyl acetate, 3-methylbutanal, l-penten-3-ol, 3-hexyl acetate, tmns- >- itxtn- -o and methyl nonanoate are prominent volatile constituents. 

Butoxyethyl 2,4-Dichlorophenoxyacetate Butoxypropyl T richlorophenoxyacetate Buttercup Yellow Butter of Antimony Butter of Arsenic Butyl Acetate N-butyl Acetate Sec-Butyl Acetate Butyl Acrylate Iso-Butyl Acrylate N-butyl Acrylate Butyl Alcohol N-butyl Alcohol Sec-Butyl Alcohol Tert-butyl Alcohol Butyl Aldehyde N-Butyl Alpha-Methyl Acrylate N-butyl Methacrylate... 

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