Bifunctionalized Allenes. Part XIII. A Convenient and Efficient Method for Regioselective Synthesis of Phosphorylated α-Hydroxyallenes with Protected and Unprotected Hydroxy Group

Abstract

Abstract:The paper describes a convenient and efficient method for regioselective synthesis of phosphorylated α-hydroxyallenes using an atom economical [2,3]-sigmatropic rearrangement of intermediate propargyl phosphites or phosphinites. These can be readily prepared via reaction of protected alkynols with dimethyl chlorophosphite or chlorodiphenyl phosphine respectively in the presence of a base.

Bifunctionalized allenes, Part XIX: Synthesis, electrophilic cyclization/addition, and coinage metal‐catalyzed cycloisomerization of phosphorylated 3‐(β‐hydroxy)allenes

“…Of particular interest are the applications of these groups as temporary transformers of chemical reactivity of the allenic system in the synthesis of eventually heterocyclic compounds. In a continuation to our previous reports on the synthesis [23] and cyclization reactions of phosphorylated 1-(α-hydroxy)- [24a,b] and 1-(β-hydroxy)allenes [24c,25] as well as phosphorylated 3-(α-hydroxy)allenes, [26] we have found a convenient and efficient method for regioselective synthesis of phosphorylated 3-(β-hydroxy)allenes by an atom economical [2,3]-sigmatropic rearrangement of the mediated hydroxysubstituted propargyl phosphite or phosphinite, which is to be used as starting materials in the electrophilic cyclization/ addition and coinage metal-catalyzed cycloisomerization reactions.…”

“…Our strategy for the synthesis of the phosphorylated 3‐(β‐hydroxy)allenes, using our experience on the preparation of the phosphorylated 1‐ and 3‐(α‐hydroxy)‐allenes as well as phosphorylated 1‐(β‐hydroxy)‐allenes, relies on the well‐precedented [2,3]‐sigmatropic shift of propargylic phosphites to allenephosphonates and propargylic phosphinites to allenyl phosphine oxides . In order to assess this approach toward the target 1,3‐bifunctionalized allenes, a range of the phosphorylated 3‐(β‐hydroxy)allenes 5 , 7‐9 was prepared by the following four‐step procedure including (i) protection of the hydroxy group in the hydroxyketone 1 , (ii) subsequent reaction with Grignard reagent and phenylacetylene to give the 6‐phenylhex‐5‐yne‐2,4‐diol 3 with protected hydroxy group at position 2, (iii) interaction with a chloride of phosphorus acid in the presence of a base, and finally (iv) [2,3]‐sigmatropic rearrangement of the mediated propargyl phosphite or phosphinite.…”

Bifunctionalized Allenes. Part XVI. Synthesis of 3-Phosphoryl-2,5-dihydrofurans by Coinage Metal-Catalyzed Cyclo-isomerization of Phosphorylated α-Hydroxyallenes

“…The starting phosphorylated α-hydroxyallenes 1 and 2 were prepared according to the established procedure [ 54 ]. CH 2 Cl 2 was distilled over CaH 2 and other organic solvents used in this study were dried over appropriate drying agents by standard methods and distilled prior to use.…”

“…These molecules can be considered a combination of an allenephosphonate or allenyl phosphine oxide and a hydroxyallene and they are supposed to have different reactivity profiles in cycloisomerization reactions. Our recent research has led to a significant result, whereby we have developed a convenient and efficient method for the regioselective synthesis of phosphorylated α-hydroxyallenes using an atom economical [ 2 , 3 ]-sigmatropic rearrangement [ 54 ]. In this paper, we present recent results of ongoing studies dedicated towards the optimization of the experimental conditions and the catalyst efficiency in the coinage metal salts-catalyzed cycloisomerization of α-hydroxyalkyl-allenephosphonates and phosphine oxides to 3-phosphorylated 2,5-dihydrofurans, which strongly improve the scope of this method.…”

Bifunctionalized Allenes. Part XV. Synthesis of 2,5-dihydro-1,2-oxaphospholes by Electrophilic Cyclization Reaction of Phosphorylated α-Hydroxyallenes

“…These molecules can be considered a combination of an allenephosphonate or allenyl phosphine oxide and a hydroxyallene and they are supposed to have different reactivity profiles in electrophilic reactions. Our recent research has led to a significant result, whereby we have developed a convenient and efficient method for the regioselective synthesis of phosphorylated α-hydroxyallenes using an atom economical [2,3]-sigmatropic rearrangement of intermediate propargyl phosphites or phosphinites, which can be readily prepared via reactions of protected alkynols with dimethyl chlorophosphite or chlorodiphenyl phosphine, respectively, in the presence of a base [55].…”