Epoxy isocyanides

A communication from Baldwin on triflic anhydride (trifluoromethanesulfonic anhydride) describes this reagent as being superior for the conversion of form-amides and vinyl formamides to isocyanides and vinyl isocyanides in yields of about 80% [1237]. Dehydration with triflic anhydride seems to be the method of choice for preparing epoxy isocyanides (see below). 

The isomerization of epoxy isocyanide 1672 to hydroxy-vinyl isocyanide 1673 has been described [1242]. This isomerization is base-mediated and the stereochemistry can be reversed by switching from lithium diisopropylamide (LDA) to lithium bis(trimethylsilyl)amide (LHMDS). The triflic anhydride method was applied to prepare 1672 [1242]. 

They have a water white color and show a high resistance to change in color with time. Generally acrylics when co-reacted with other resins, such as epoxy and isocyanide, show a greater durability. They have found a wide use in trains, aeroplanes and buses. 

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