BuLi-triggered phospha-Brook rearrangement: efficient synthesis of organophosphates from ketones and aldehydes

Synthesis and Reactions of α-Hydroxyphosphonates

“…A new approach of this transformation is when the Pudovik reaction of benzaldehydes and dialkyl phosphites and the subsequent rearrangement of the so-formed α-hydroxyphosphonate 1 take place in “one-pot”, under the same conditions. The synthesis of benzyl phosphates 56 directly from an oxo compound and a P -reagent was efficiently catalyzed by butyllithium ( Scheme 28 , Route “a”) [ 142 ] as well as by DBU ( Scheme 28 , Route “b”) [ 143 ]. The tandem Pudovik reaction and rearrangement was also reported in the presence of superbases 57 ( Scheme 28 , Route “c”) [ 144 ].…”

Synthesis and Characterization of New Variously Substituted Allylic Phosphates

“…Inspired by the recent results of Chakravarty et al [23], we have also tested the direct preparation of phosphates 3 from aldehydes 1 and diethyl phosphite in the presence of BuLi via the phospha-Brook rearrangement, but the desired products were obtained only after 48 h at 60°C in poor yields.…”

“…Dineshkumar and Prabhu have reported an efficient iodine-catalyzed phosphorylation of alcohols in the presence of H 2 O 2 for the preparation of various phosphates [22]. More recently, the synthesis of organophosphates from aldehydes through a BuLi-triggered phospha-Brook rearrangement was described [23]. However, the use of variously substituted aldehydes or allylic alcohols as partners in these reactions is rarely reported in the literature [24].…”

Regio‐Selective Phosphation and Phosphonation of 9‐Fluorenones

“…Also, the migratory propensity of phosphonates in cyclopentadienyl systems is not known and may have implications in the modifications of other related system as well . Notably, Phospha‐Brook rearrangement in carbonyls without an activating group like ketone or ‐CCl 3 at α ‐position is particularly challenging and requires strong basic condition such as n ‐BuLi . The preceding discussion makes it evident that examination of behaviour of fluorenones towards H ‐phosponates is of great intrigue.…”