Isocyanide, benzyl butyl

Benzopyran-3-one, l,4-dihydro-6,7-dimethoxy-], 55, 45 Isocyamde, benzyl-, 55, 98 Isocyanide, butyl-, 55, 98 ISOCYANIDE, tert-butyl- [Isocyamde, 1,1-dimethylethyl-], 55, 96 Isocyamde, cyclohexyl-, 55, 98 Isocyamde, dodecanyl-, 55, 98 Isocyamde, ethyl, 55,98 Isocyamde, methyl, 55, 98 Isocyamde, phenyl-, 55, 98 (-)-2,3 4,6-Di-0-isopropylidene-2-keto-L-gulomc acid, hydrate [L-jcy/o-2-Hex-ulosomc acid, bis-<9-( 1 -mcthylcthyl-ldene)-], 55,80, 81 ISOXAZOl F, 3-(4-chlorophenv1)-5-(4-methoxyphenyl)-, 55, 39 Isoxazole,5 -(4-chloropheny l)-3-(4-me th-oxyphenyl)-, 55,42... 

Isocyanate, chlorosulfonyl-, 56, 41 Isocyanate, 2-propyl-, 56, 96 Isocyanide, benzyl-, 55, 98 Isocyanide, butyl-, 55, 98 ISOCYANIDE, tert-bulyl-, 55, 96 Isocyanide, cyclohexyl, 55, 98 Isocyanide, dodecanyl-, 55, 98 Isocyanide, ethyl-, 55, 98 Isocyanide, methyl-, 55, 98 Isocyanide, phenyl-, 55, 98 Isophorone, 57, 113 Isopropenyl acetate, 57, 113 Isopropyl alcohol, 58, 78,157 Isopropyl ether, 58, 45, 52 Isopropyl fluoride,58,78 Isopropylurea-polystyrene, 56, 96 Isoquinohne, 56, 20... 

The present procedure is the best way of preparing aliphatic isocyanides boiling above ethyl isocyanide. It has been applied to the synthesis of the following isocyanides 6 isopropyl (38%), -butyl (61%), te -butyl (68%), and benzyl (56%). In preparing isopropyl isocyanide or teri-butyl isocyanide, the petroleum ether should be of boiling point 30-35°, as otherwise it is difficult to separate these low-boiling isocyanides in the indicated yield, and,... 

This product is sufficiently pure for the preparation of phenylacetic acid and its ethyl ester, but it contains some benzyl iso-cyanide and usually develops an appreciable colour on standing. The following procedure removes the isocyanide and gives a stable water-white compound. Shake the once-distilled benzyl cyanide vigorously for 5 minutes with an equal volume of warm (60°) 50 per cent, sulphuric acid (prepared by adding 55 ml. of concentrated sulphuric acid to 100 ml. of water). Separate the benzyl cyanide, wash it with an equal volume of saturated sodium bicarbonate solution and then with an equal volume of half-saturated sodium chloride solution. Dry with anhydrous magnesium sulphate and distil under reduced pressure. The loss in washing is very small (compare n-Butyl Cyanide, Section 111,113, in which concentrated hydrochloric acid is employed). 

Reaction of a primary amine with chloroform in the presence of an alkali hydroxide gives the isocyanide. This reaction has long been known for qualitative detection of primary amines but it often gives good yields on a preparative scale. It usually occurs exothermally on mere mixing of the components. By using benzene as solvent Malatesta637 achieved yields of 80-85% from some aliphatic and arylalkyl amines (butyl, isopentyl, pentyl, benzyl). 

Base-mediated (Formal) Cycloadditions. KHMDS, as well as other bases, have been used in the synthesis of pyrroles via a formal [3 + 2] cycloaddition of metalated isocyanides with ethyl cyclopropylpropiolate. The effect of the nature of the base on the ratio of the desired p3nrole product to the undesired ketone byproduct was investigated. The proposed mechanism consists of a formal cycloaddition of the metalated isocyanides across the triple bond, followed by a 1,5-hydrogen shift and protonation. The reaction between benzyl isocyanide and f-butyl cyclopropylpropiolate mediated by f-BuOK (2 h, rt) afforded a mixture of both the products in 96% combined yield and 1 1 ratio (eq 90). Similar results were achieved in reactions mediated by KHMDS both at rt and —78 °C (93% and 86% combined yields of 1 1 mixtures) (eq 90). The replacement of KHMDS with NaHMDS and LiHMDS led to a nearly exclusive formation of the undesired ketone product. The content of the undesired ketone product appeared to increase when harder cations were used. Accordingly, the application of t-BuOCs (2 h, rt) afforded 91% combined yield of the two products in a 96 4 ratio favoring the heterocycle (eq 90). 

With substrates featuring a more energetic, multiply unsaturated polarized bonding scheme, like carbodiimides or isocyanides, a [2+2] cycloaddition reaction to the C=Y bond subsequent to the preliminary nucleophilic attack of the benzyl ligand could be observed [68] (Scheme 17). The same cycloaddition was also observed with those substrates and the corresponding iodinated yttrium complex, which also reacted with tert-butyl phosphaalkyne [67]. However, no subsequent [2+2] cycloaddition was observed with pivalonitrile or adamantly azide on the benzylated complex. 

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