Isocyano-isocyanates

A novel and unique class of orthogonal divalent compounds has recently been filed for European patent application, namely isocyano-isocyanates [1288]. 

The isocyano-isocyanates 1752a-d can easily be prepared in yields of 50-78% by parallel reaction steps in a one-pot synthesis from monoformyldiamines 1751a-d... 

As an example supporting the above statements regarding parallel reaction steps, parallel reactions of isocyano-isocyanate 1752b at both the isocyano and iso-cyanato groups can be accomplished in a one-pot procedure, whereby methanol is added to the isocyanato group and a Passerini three-component reaction (P-3CR) with benzaldehyde and acetic acid occurs at the isocyano group, simultaneously affording both the urethane and Passerini product moieties in l-N-(0-methyl-carbamato)-10-N -[(2-acetoxy)-3-phenylacetamido]decane 1753 in 92% yield [1289]. 

Allenes react with isocyanates to give the a-alkylidene-/Mactams. The highly reactive chlorosulfonyl isocyanate (CSI) is often used. Initial nucleophilic attack of the central allenic carbon atom to the central isocyano carbon atom produces an allylic cation intermediate, which cyclizes to the /i-lactam. 

An alternative method for preparing isocyano carboxylic esters using methyl isocyanate, acetone, and chloroformic acid benzyl ester was also described by the author and illustrated in Eq. 1 ... 

TRIFLUOROMETHYLPHENYL) ESTER see TKJ250 ISOCYANIC ACID, p-XYLYLENE ESTER see XSS260 ISOCYANIDE see COI500 1-ISOCYANO-4-NITROBENZENE see IKH780 ISOCYANURIC ACID, DICHLORO- see DGN200 ISOCYANURIC ACID, DICHLORO-, POTASSIUM SALT see PLDOOO... 

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