Formamidines carbodiimides

HETEROCYCLES Dicyclohexyl-carbodiimide. Formamidine acetate. Thionyl chloride. 

Addition of an organometallic reagent to carbodiimides provides excellent access to formamidines with high yields.263,264... 

Examples of insertion reactions include Grignard or alkyl lithium compounds which react with carbodiimides to give formamidines 389 after hydrolysis. ... 

The reduction of carbodiimides affords formamidines 709. Examples include reaction with NaBH4 or catalytic hydrogenation. ... 

When the less hindered 2,4-tolylene diisocyanate is reacted with a phospholene oxide catalyst linear oligomeric carbodiimides are obtained which have been reacted with a variety of nucleophiles to give poly(ureas), poly(acyl ureas), poly(formamidines) and poly-(guanidines) by addition across the N=C=N group. Also, reaction of the oligomeric carbodiimides with acrylic or methacrylic acid affords linear polymers, which can be further polymerized by free-radical type processes. Also, reaction of the carbodiimide oligomers obtained from 2,4-TDI with adipic acid in DMF produces a polyureid. ... 

Hydrosilylation of carbodiimides proceeds only at 140-200°C in the presence of PdClj or Rh(PPh3)3Cl to give )V-silylformamidines 3. The fV-silylformamidine thus obtained reacts with methanol and acyl chlorides to afford the corresponding formamidines and A -acyl formamidines, respectively ... 

Similar reactions occur on treatment of benzalaniline, carbodiimides, phenyl isocyanate and N-sulfinylaniline with iminium chlorides For example, from chlorodimethylformiminium chloride and phenyl isocyanate the 1 1 adduct CXXXVII is obtained, which on thermolysis (with elimination of carbonyl chloride) or hydrolysis yields the formamidine CXXXVIH... 

Copper salt catalyzed G-insertion of isonitriles, CO, or diazo compounds into NH-bonds of amines gives good yields of form-amidines, formamides, or N-alkylated products respectively Recently, the analogous C-insertion of isonitriles into OH-bonds of alcohols has been reported . A variety of compounds, otherwise difficult to obtain, such as certain carbodiimides, acylamidines, or isonitriles, can be prepared by H2S-elimination with acylchloro-formamidines . 

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