F-Butyl nitrile

A study of the regioselectivity of the 1,3-dipolar cycloaddition of aliphatic nitrile oxides with cinnamic acid esters has been published. AMI MO studies on the gas-phase 1,3-dipolar cycloaddition of 1,2,4-triazepine and formonitrile oxide show that the mechanism leading to the most stable adduct is concerted. An ab initio study of the regiochemistry of 1,3-dipolar cycloadditions of diazomethane and formonitrile oxide with ethene, propene, and methyl vinyl ether has been presented. The 1,3-dipolar cycloaddition of mesitonitrile oxide with 4,7-phenanthroline yields both mono-and bis-adducts. Alkynyl(phenyl)iodonium triflates undergo 2 - - 3-cycloaddition with ethyl diazoacetate, Ai-f-butyl-a-phenyl nitrone and f-butyl nitrile oxide to produce substituted pyrroles, dihydroisoxazoles, and isoxazoles respectively." 2/3-Vinyl-franwoctahydro-l,3-benzoxazine (43) undergoes 1,3-dipolar cycloaddition with nitrile oxides with high diastereoselectivity (90% de) (Scheme IS)." " ... 

Enamines or imines can form pyridines by cyclization to a nitrile group, as shown in the production of compound (48). Alternatively, the nitrogen atpm of the nitrile can be made more nucleophilic by attack on the carbon atom by an external nucleophile. Ammonia causes cyclization of the dienamines (53) (77JHC1077) and (54) (78JAP(K)786878l) in both cases, elimination of the amine introduces the extra double bond. Dimethylamine or piperidine cause cyclization of l-cyano-2,5,5-trimethylhex-l-en-3-yne to the f-butyl-pyridine (55). There are a few other examples of the synthesis of bicyclic compounds from... 

Trialkylboranes react rapidly and in high yields with a-halo ketones,1546 a-halo esters,1549 a-halo nitriles,1550 and a-halo sulfonyl derivatives (sulfones, sulfonic esters, sulfonamides)1551 in the presence of a base to give, respectively, alkylated ketones, esters, nitriles, and sulfonyl derivatives.1552 Potassium /-butoxide is often a suitable base, but potassium 2,6-di-f-butyl-phenoxide at 0°C in THF gives better results in most cases, possibly because the large bulk of the two /-butyl groups prevents the base from coordinating with the R3B.1553 The trialkylboranes are prepared by treatment of 3 moles of an alkene with 1 mole of BH,... 

Michael Addition. Titanium imide enolates are excellent nucleophiles in Michael reactions. Michael acceptors such as ethyl vinyl ketone, Methyl Acrylate, Acrylonitrile, and f-butyl acrylate react with excellent diastereoselection (eq 21 ). - Enolate chirality transfer is predicted by inspection of the chelated (Z)-enolate. For the less reactive unsaturated esters and nitriles, enolates generated from TiCl3(0-j-Pr) afford superior yields, albeit with slightly lower selectivities. The scope of the reaction fails to encompass p-substituted, a,p-unsaturated ketones which demonstrate essentially no induction at the prochiral center. Furthermore, substimted unsamrated esters do not act as competent Michael acceptors at all under these conditions. 

If we dissolve f-butanol in a nitrile as solvent and add strong acid, a reaction does take place. The acid does not protonate the nitrile, but does protonate the alcohol to produce the f-butyl cation in the usual way. This cation is reactive enough to combine with even such a weak nucleophile as the nitrile. 

A solution of the nitrile (2.77 g, 14.5 mmol) and powdered 85% KOH (7.66 g, 116 mmol) in f-butyl alcohol (30 mL) was heated at reflux for 1.5 h. The reaction mixture was then cooled to room temperature, diluted with water (30 mL), and acidified with 1 N HCl (116 mL, 116 mmol) to give a slurry that was filtered and rinsed with water and then Et2O (40 mL). The solid was dried in a vacuum oven at 40 °C to give 2.39 g (79%) of the amide. 

The present Strecker-type reactions were successfully applied to asymmetric reactions. In the presence of 10mol% Yb(OTf)3 and 100mol% 2,6-di-f-butyl-4-methyl-pyridine (DTMP), the three-component reaction of benzaldehyde, (i5,2/ )-(+)-2-amino-1,2-diphenylethanol, and TMSCN proceeded smoothly at -45°C, to afford the corresponding a-amino nitrile in an excellent diastereoselectivity. In the reaction using cyclohexanecarboxaldehyde, the selectivity decreased slightly ... 

IV), and nitriles (V) by reaction with f-butyl lithioacetate, (5, 371), lithio N,N-dimethylacetamide, and lithio acetonitrile, respectively, followed by elimination of trimethylsilanol (Peterson reaction). 

The use of thienyl Grignard reagents, and more recently lithiated thiophenes, has been extensive and can be illustrated by citing formation of oxythiophenes, either by reaction of the former with f-butyl perbenzoate or the latter directly with bis(trimethylsilyl) peroxide or via the boronic acid, the synthesis of thiophene carboxylic acids by reaction of the organometallic with carbon dioxide, the synthesis of ketones, by reaction with a nitrile, or alcohols by reaction with aldehydes, by the reaction of 2-lithiothiophene with A -tosylaziridine, and by syntheses of thieno[3,2- ]thiophene and of dithieno[3,2- 2, 3 - /]thiophene. Some of these are illustrated below. 

Palladium-catalyzed a-Arylation of Carbonyl Compounds and Nitriles. A variety of bases have been used in the palladium-catalyzed a-arylation of carbonyl derivatives. The pKa of the carbonyl moiety determines the choice of the base. For instance, a-arylation with ester derivatives requires the use of strong bases such as NaHMDS. The best yields for the arylation of t-butyl acetate were reported with LHMDS, whereas the arylation of f-butyl propionate occurred in higher yields in the presence of NaHMDS (eq 12). ... 

Mioskowski and co-workers reported the use of Burgess salt, DAST, ox-alyl chloride and phosphorus oxychloride for dehydration of nitroaUcanes 13 among which they found DAST to be the best reagent [87]. Recently, a microwave-assisted generation of nitrile oxide 5 under the catalytic influence of 4-(4,6-dimethoxy[l,3,5]triazin-2-yl)-4-methylmorpholinium chloride (DMTMM)/DMAP [88] has been described. However, di-f-butyl dicarbonate (Boc20)/DMAP, a method reported by Basel and Hassner, allows the dehydration of nitroalkanes 13 under much milder conditions (Scheme 4) [89]. In fact, this has become an efficient method because of the innocuous nature of the side products (f-BuOH and CO2), which simplifies the purification of the ultimately desired isoxazoHne product. 

Krishnacharya G. Akamanchi of the Institute of Chemical Technology, Matunga, Mumbai has shown Tetrahedron Lett. 2007, 48, 5661) that f-butyl hypochlorite and NaNj will convert an aldehyde 18 to the acyl azide 19. The acyl azide 19 can be carried on to the nitrile 20, or, on warming, to the inverted isocyanate 21. 

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