Tert.-butylisocyanide

Cyclization takes place when tert-butylisocyanide, benzaldehyde, anilinium chloride, and carbonyl(dicyano)cyclopentadienyl ferrate are reacted, the carbene complex 42 being the result (95JOM(491)135). /50-butyraldehyde, tert-butyl isocyanide, ammonium hexafluorophosphate, and [(T -Cp)Fe(CO)(CN)2] give the cationic bis-carbene 43. 

A variety of cyclic products have been prepared from educts containing carbonyl as well as carboxylic groups. Thus, Hanusch-Kompa and Ugi prepared a large number of five-membered cyclic gamma-lactam compounds like 44 from levulinic acid. Other carbonylic acids can lead to compounds like 45, which is made from phthalaldehyde acid, valine methylester, and tert-butylisocyanide. The products like 46 and 47 can result from the U-4CR and further cyclization. 

The variety of educts and products of the higher MCRs is illustrated here. Product 72 (Scheme 1.18) is formed from the five functional groups of lysine, benzaldehyde, and tert-butylisocyanide. The synthesis of 73 is achieved with hydrazine, furanaldehyde, malonic acid, and the isocyano methylester of acetic acid, compound 74 results from the reaction of benzylamine, 5-methyl-2-furanaldehyde, maleic acid mono-ethylester, and benzylisocyanide. ° Zhu et al. prepared a variety of related products, such as, 75, from (9-amino-methyl cinnamate, heptanal, and a-isocyano a-benzyl acetamides. 

Zirconium-benzyne complexes have been used rather extensively in organic synthesis.8 45 For this purpose, one particularly important characteristic of zirconium-aryne complexes is that olefin insertion into the Zr—C bond occurs stereospecifically. Thus, when generated in situ, the zirconium-benzyne complex (45) reacts with cyclic alkenes to give exclusively the cis-zirconaindanes (46), which upon treatment with electrophiles provide access to a variety of m-difunctionalized cycloalkanes (47-49) (Scheme 5).46 For example, carbonylation of intermediate 46 affords tricyclic ketone 49, reaction with sulfur dichloride gives thiophene 48, and reaction of 46 with tert-butylisocyanide followed by I2 gives 47 via 50 and, presumably, intermediate 51 [Eq. (12)]. 

Scheme 7.5 Preparation of bis(l,5-cyclooctadiene)platinum(0) (19) and its reactions with ethene to tris(ethene)platinum(0) (20) and with tert-butylisocyanide to the trinuclear platinum cluster 21 (R = fBu)...

Palladinm Bis-[tert.-butylisocyanid]-chloro-methoxycarbonyl-XIII/9b, 877... 

Acetyl-(tert.-butylisocyanid)-carbo-nyl-(j 5-cyclopentadienyl)-XIII/9a, 397... 

Hexakis(tert-butylisocyanide)triplatinum (Pt3[CN-/-Bu],5) reacted with 2,3-diphenylcycloprop-enone to give /t-2-oxo-l,3-diphenylpropanediylidenebis[bis(t< -Tt-butylisocyano)platinum] 4. Synthesis of the complex involves C-C double-bond cleavage in cyclopropenone the resulting C3 fragment bridges symmetrically the two platinum atoms. ... 

Between 1964 and 1967, many different ratios and concentrations of isobutyraldehyde-(S)-a-phenylethylamine, benzoic acid and tert-butylisocyanide in methanol at 0 °C were investigated [4,8,28]. In one series of experiments the dependence of the electrical conductivity of the Schiff base and its carboxylic acid was determined, while in a second series the relationship between educt concentration and the ratio of diastereoisomeric products was investigated by measurement of their optical rotation. 

The major difference between the reactions of the isoelectronic carbon monoxide and tert-butylisocyanide with 2 comes, most probably, from the different stability of the hypothetical obtainable rhodium cations. The complex [Rh(CNBu )4]+, a stable and well-known cation, allows the formation of 14, while the relatively low stability... 

Caution. Chromium, molybdenum and tungsten hexacarbonyls are volatile solids (Cr > Mo > W) and like all metal carbonyl compounds should be considered to be toxic. tert-Butylisocyanide has a pungent odor, and although many isocyanides are reported to exhibit no appreciable toxicity to mammals, it should still be handled with care. Carbon monoxide is evolved in these reactions and being an odorless, toxic gas, care should be exercised to carry out the reactions in an efficient ventilation hood with the apparatus venting into a well-ventilated region of the hood. 

The catalyst PdO (0.020 g 0.16 mmol), [M(CO) ] (2.0 mmol M = Cr, 0.440 g M = Mo, 0.528 g M = W, 0.704 g), and toluene (40 mL) are combined in the reaction flask. The mixture is heated to boiling and the appropriate amount of tert-butylisocyanide required to achieve mono-(2.05 mmol, 0.230 mL), di- (4.1 mmol, 0.460 mL), or trisubstitution (6.15 mmol, 0.690 mL) is added by microsyringe. The reaction mixture is heated under reflux until completion of the reaction as monitored by IR spectroscopy or thin layer chromatography (Table I). The mixture is allowed to cool to room temperature and Altered through a fluted filter paper to separate the catalyst. The solvent is removed under vacuum to give the crude products. Product purification employed the same procedures detailed above for the cobalt(II) chloride-catalyzed reaction. ... 

MoN3CjgH27, Molybdenum, tris(tert-butylisocyanide)tricarbonyl-, /ac-, 28 143 OjMoNaCgH5.2C4H 10O2, Molybdate(l -), tricarbonyl( i -cyclopentadienyl)-, sodium, compd. with 1,2-dimethoxyethane(l 2), 26 343 OgMoPjCggHgg, Molybdenum,... 

In a one-pot three-component reaction, methyl 2-formylbenzoate, 2-aminopyrazine, and tert-butylisocyanide were subjected to a tandem process, namely ... 

In a three-component one-pot procedure, 2-aminophenol, 4-nitrobenzaldehyde, and tert-butylisocyanide were reacted in ethanol in the presence of a catalytic amount of TosOH at reflux temperature for 6h. After aqueous workup, a product A was isolated in 91% yield. 

H3 yClNjOgOsPa r CarbonylnitrosyKp-tolyl isocyanide)-bis(triphen-ylphosphine)osmium(O) perchlorate, 42B, 645 CnsH4 2P2Pd2 r M (Cyclopentadienyl)-/x (2-methylallyl)-bis(triphenyl-phosphine)-dipalladium(Pd-Pd), 43B, 1026 C4 5H4 3CICUN3O4P2 r (tert-Butylisocyanide)[N,N -bis(o-(diphenylphos-phino)benzylidene]ethylenediamine-P,P, N]copper(I) perchlorate,... 

Andersen RA (1979) Dialkylbis[bis(trimethylsilyl)amido]zirconium(IV) and -ha iium(IV). Preparation and reaction with carbon dioxide and tert-butylisocyanide. Inorg Chem 18 2928-2932... 

More interesting results have been obtained by polymerization of optically active (+)-or (-)-sec-butylisocyanide (XIIIc) in the presence of nickel chloride. A resolution of racemic poly(tert-butylisocyanide) by column chromatography on insoluble poly[(+)-sec-butylisocyanide] as supporting medium appeared to be successful. 

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