Isocyanide, benzyl, reaction with

A first terminal imido complex of nickel (121) was prepared according to Equation (3).468 The synthesis goes via the Ni11 amido compound (122) and uses the steric bulk of the arylimido group for stabilization. The Ni11 center in (121) is planar and three-coordinate. Reaction of (121) with CO or benzyl isocyanide leads to formal nitrene transfer with formation of (124) and (125), respectively. Further reaction with CO liberates the isocyanate and carbodiimide (Equation (4)). 69... 

Benzyl isocyanide is a useful precursor of compounds containing the ot-benzylamino moiety. Substituted styrenes, vinyl isocyanides, 2-oxa-zolines, 1-pyrrolines, imidazoles, and a-amino acids and ketones can be obtained by metalation of isocyanides with butyllithium12 or copper salts,13 and subsequent reaction with various electrophiles.12... 

An alternative route involves the nucleophilic substitution of an alkyl or benzyl halide with a cyanide ion. Two reactions are possible, leading to an isocyanide (R N=C) or a cyanide (R -ON). 

If a C-substituted derivative of TOSMIC is used in the reaction, the product is a 1,4,5-trisubstitutcd imidazole. Such substituted isocyanidcs can be made either by dehydration of the iV-(a-tosylalkyl)formamide, or by alkylation of an appropriate isocyanide followed by reaction with tosyl fluoride. It is also possible to alkylate TOSMIC directly using phase transfer conditions 13], Such alkylations work best with primary alkyl halides (75-95%), with the isopropyl (40%), allyl (75%) and benzyl (80%) derivatives proving quite accessible. 

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). 

Tosylmethyl isocyanide (TosMIC) was employed in a key step for the synthesis of bicyclic heterocycles from L-glutamic acid <01H(55)2099>, while benzyl isocyanoacetate was utilized for reaction with a-acetoxynitro compound 41 to yield the pyrrole 42, an intermediate in the synthesis of (+)-deoxypyrro oline, a putative cross-link of bone collagen <01JOC11>. 

To further complicate the picture, the related isocyanide-substituted cation, [Os(=Cp-tolyl)(CNp-tolyl)(CO)(PPh3)2], undergoes a fast thermal reaction with HCl as depicted in Scheme 3. The cationic carbene complex produced is converted by treatment with LiEt3BH to the neutral substituted-benzyl complex labelled B in Scheme 3. The overall two-step transformation of A into B is a good example of the conversion of a metal-carbon triple bond to a metal-carbon single bond by sequential addition of "H+ followed by "H-" [11]. 

Methoxycarbonylcycloheptatriene is conveniently obtained from tropy-lium tetrafluoroborate via reaction with cyanide ion or benzyl isocyanide and hydrolysis. ... 

The synthesis of highly substituted rigid tricyclic nitrogen heterocycles via a tandem four-component condensation (the Ugi reaction)/intramolecular Diels-Alder reaction was investigated in both solution and solid phase [24]. The Ugi reaction in MeOH (Scheme 4.2) involves the condensation of furylaldehydes 17, benzylamine 18, benzyl isocyanide 19 and maleic or fumaric acid derivatives 20, and provides the triene 21 which immediately undergoes an intramolecular Diels-Alder reaction, affording the cycloadduct 22 in a diastereoisomeric mixture with high yield. 

Indoles were synthesized by the intramolecular functionalization of a benzylic C-H bond. Hence, the reaction of 2,6-xylyl isocyanide with a ruthenium complex led to 7-methylindole (Equation (36)). 

Muetterties and co-workers (21, 22, 60, 139) found that addition of deficiencies of isocyanides to Ni(COD)2 gave the clusters Ni4(CNR)7 (R = Bu, C6H,) and Ni4(CNBu )6. With isopropyl and benzyl isocyanides, dark brown and red solids of compositions Ni4(CNPr )6 and (Ni4(CNCH2Ph)4 Jt (x unknown) were obtained. Corresponding reactions in the presence of L [L = P(OMe)3, CNMe] gave Ni7(CNBu )6L. 

The synthesis of BENZYL ISOCYANIDE from benzaldehyde via reductive amination with 5-aminotetrazole followed by oxidation of the resultant amine with sodium hypobromite provides a general method for the synthesis of isocyanides. The preparation of BIS(2,2,2-TRICHLOROETHYL) AZODICARBOXYLATE makes available an alternative to dimethyl azodicarboxylate that is not only more reactive in Diels-Alder reactions but whose ester groups can be removed under neutral conditions. 

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