Isocyanide t-butyl

Below 100 °C tri-t-butyldiaziridinimine (176) only undergoes inversion at the exocyclic nitrogen, as evidenced by coalescence of NMR signals at about 50 °C. Heating for 1 h to 150 °C, however, results in clean formation of ( )-azoisobutane and t-butyl isocyanide. 

Diaziridinone (167) was also obtained in attempted syntheses of oxaziridinimine (282) from either di-t-butylcarbodiimide and peracid, or nitrosoisobutane and t-butyl isocyanide, probably by valence isomerization of the transient (282) (70JOC2813). 

Ugi and Domling have shown that the U-4CR can also be combined with other MCRs, thus creating sequences which involve up to nine different substrates [33]. An example of such an approach is the combination of an Ugi-4CR with the as-yet not mentioned Asinger reaction (A-3CR or A-4CR). The latter allows the formation of thiazolines from ammonia, carbonyl compounds and sulfides [34]. As shown in Scheme 9.7, a mixture of a-bromoisobutyraldehyde, isobutyraldehyde, sodium hy-drogensulfide and ammonia yields the imine 9-38 which, by reaction with t-butyl-isocyanide, methanol, and C02, led to the final product 9-39 [35]. 

Intramolecular nitrile oxide cycloaddition. The conjugate addition of t-butyl isocyanide to a nitroalkene can generate a nitrile oxide, which can be trapped intramolecularly by a double bond to form an isoxazoline. 

Green, M., Howard, J.A.K., Murray, M., Spencer, J.L. and Stone, F.G.A. (1977) Synthesis and crystal and molecular structure of tris-p-(t-butyl isocyanide)-tris(t-butyl isocyanide)-triangMlo-triplatinum. J. Chem. Soc., Dalton Trans., 1509-14. 

The same approach was recently used for the synthesis of a cyclopeptoid as potential inhibitor of the Tat/TAR complex of the HfV-1 virus (Scheme 24) [94, 95]. Two Ugi reactions were used to prepare fragment b that was coupled to fragment a to afford linear precursor c. The macrocyclic peptidomimetic d was obtained after cyclization employing Ugi reaction of amino acid c with paraformaldehyde and t-butyl isocyanide. 

The acid-catalyzed reaction of oxetanes with t- butyl isocyanide gives 2-iminotetra-hydrofurans, boron trifluoride etherate being used as catalyst (equation 26). The authors proposed that the isocyanide reacts with the protonated oxetanes by an N2 mechanism (70S475). 

A tentative reservation exists about this work. As reported, in a communication, it as yet gives no explanation for the unexpected solubility of poly(r t-butyl isocyanide) in chloroform, nor does it describe a safeguard against the mutual solubility, i.e. plasticization, of polyisocyanides, which is a possibility between the non-crosslinked, otherwise insoluble support medium and the mobile solute. Yet, the rotation data is compelling. 

The t-butyl isocyanide complexes of nickel(O) are used as starting materials for the synthesis of a number of complexes with unsaturated groups n bonded to the nickel atom in reactions similar to those given by dioxygen or diazo complexes (Sections 50.2.7.2 and 50.2.6.3). 

In 1976, Saegusa reported the copper(I) t-butoxide-promoted deoxygenation of C02 by t-butyl isocyanide to produce t-butyl isocyanate and CO (Equation 6.13) [111a]. 

When a mineral or Lewis acid replaces the carboxylic component in the Passerini reaction, the final products are usually a-hydroxyamides. Also in this case, when chiral carbonyl compounds or isocyanides are employed, the asymmetric induction is, with very few exceptions, scarce [18, 19]. For example, the pyridinium trifluoroacetate-mediated reaction of racemic cyclic ketone 14 with t-butyl isocyanide is reported to afford a single isomer [19] (Scheme 1.7). This example, together with those reported in Schemes 1.3 and 1.4, suggests that high induction may be obtained only by using rigid cyclic or polycyclic substrates. 

The reaction of propiophenone with thionyl chloride in pyridine provides 3,4-diben-zoylthiophene (79H(12)46l). The boron trifluoride catalyzed reaction of benzophenone with t-butyl isocyanide gives an indole derivative (Scheme 84b) (67TL3881). Another... 

Caution. Although t-butyl isocyanide is apparently only weakly toxic,1 its odor is unpleasant, and all operations involving isocyanides should be conducted in a fume hood. 

Alkylation of (Et0)2P(0)CH(CN)NMe2 with EtCHO in CH2C12658 under reflux for 1-3 h gave 50% of EtCH=C(CN)NMe2. Nucleophilic addition of t-butyl isocyanide to aldehyde acetals in the presence of TiCl4 afforded / -alkoxycyanoenamines R2OCR1= C(CN)NHCMe3 (R1 = H, Me, Et, Pr, i-Pr, hexyl, Ph R2 = Me, Et)659. 

Cyanation of acetals. Reaction of acetals with t-butyl isocyanide catalyzed by TiCU results in cyanohydrin ethers in high yield. A similar reaction with ethylene acetals results in spirolactones. 

HN(t-Bu)COC6H2Me3. t-Butyl isocyanide also inserts into the chromium-carbon bond of the mesityl complex, but only a single insertion is observed, and Cr(=N-t-Bu)2 ] -[t-BuN=C(C6H2Me3)] (C6H2Me3) is formed. An -aminoacyl is also the product of the reaction between Cr(=N-t-Bu)2Cl2(t-BuNC) and methyllithium. Presumably, methyl replaces one of the chlorides, then migrates to the isocyanide carbon to give Cr(=N-t-Bu)2 [ 2-[t-BuN=C(Me)] Cl]. 

The related ) -immoacyl complexes (124) are known ()] -C=N). These may be prepared by reaction of [Fe(CO)2(PMe3)2(Me)I] with t-butyl isocyanide, through an equilibrium with ] -iminoacyl complex (125). The equilibration is catalyzed by halide ion, NOs, and C104, but not by BF4, PFe , or BPlu consequently, the pure compounds are isolated by precipitating the BPli4 salt from the mixture. The mechanistic details of the equilibrium have been investigated in detail. ... 

The parent TMM complex (190 R = H) undergoes photochemical ligand substitution with trifluorophosphine or trimethylamine Al-oxide assisted substitution with tertiary phosphines or t-butyl isocyanide (Scheme 5A) Trimethylamine A-oxide assisted substitution using isoprene as the incoming ligand results in C-C bond formation to afford the bis-TT-allyl complex (197). An intramolecular version of this reaction is also known.The parent complex (190 R = H) reacts with electrophiles. Addition of HCl or Br2 gives the methallyl complexes (192) and (198), respectively. Tetrafluoroethylene adds across the Fe bond to afford (199) under photochemical conditions. Complex (190) undergoes Friedel-Crafts-type acylation with... 

Recombination rates range from 10 to 10 M s, with similar values obtained by nanosecond measurements, whereas photodissociation yields are low and range from 0.03 -0.08. These low yields have been interpreted in terms of rapid relaxation of the photoexcited six-coordinate complex competing with ligand release. Other five-coordinate complexes are also formed on picosecond photolysis for example, a protoheme dimethyl ester bis(t-butyl isocyanide) in pure t-butyl isocyanide or in toluene. This photolysis results in the loss of one isocyanide ligand to produce an electronically excited five-coordinate complex, which decays to the ground state within 40 ps. The recombination rate for the formation... 

The reversible reaction of chloroiron(III) octaethylisobac-teriochlorin (or the Br, NCS, or PhS analog) with r-acid ligands such as carbon monoxide, t-butyl isocyanide or PF3 in toluene solution produces EPR spectra at 77 K that are indicative of a r-cation radical (equation 16) ... 

Urethanes. Methyl carbamates (1) can be prepared from primary or secondary amines, alkyl halides, and carbon dioxide in a reaction promoted by copper(I) /-butoxide (equation I). The ligand t-butyl isocyanide can be replaced with tri-n-butylphosphine. Copper(I) f-butoxide is more effective than other copper salts. In the case of diethylamine, the intermediates a and b were isolated and b was converted to the methyl carbamate in 86% yield. 

C0)5M[S(CH2R )R ]> with BuLi and subsequent alkylation. Reaction of these thiometal complexes with BuLi in the presence of a 7t-acid ligand L (t-butyl isocyanide, phosphanes, phosphites) produces after alkylation complexes in which another CO ligand is replaced by L... 

Carbon-transition metal bonds can also be formed by cocondensing transition-metal atoms with isonitriles. Thus, using Ni and Fe with t-butyl isocyanide, methyl isocyanide, cyclohexyl isocyanide and vinyl isocyanide the NiL4 and FeL, complexes are formed. Palladium cocondensed with isonitriles yields PdLj polymeric structures with terminal and bridged isonitrile ligands ... 

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