GRAPHICAL ABSTRACT
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Abstract
λ3-phosphahexatrienes were prepared from ethoxyvinyl phosphinophosphonates using the phospha-Wittig–Horner reaction. The title compounds can be easily prepared in three steps starting from dichlorophosphines with good overall yields. Although these were found to be thermally unstable, these can be trapped, for instance, with methanol. The resulting methoxyphosphines are isolated in high yields in case of aldehyde starting materials with more bulky substituents.