(E)-Selective Horner–Wadsworth–Emmons reaction of aldehydes with bis-(2,2,2-trifluoroethyl)phosphonoacetic acid

Abstract

The stereoselective Horner-Wadsworth-Emmons reaction of aldehydes with bis-(2,2,2-trifluoroethyl)phosphonoacetic acid utilizing i-PrMgBr afforded (E)-α,β-unsaturated carboxylic acids as the major products. bis-(2,2,2-Trifluoroethyl)phosphonoacetic acid was prepared by enzymatic hydrolysis of the corresponding methyl ester with porcine liver esterase.

A Practical and Convenient Protocol for the Synthesis of (E)-α,β-Unsaturated Acids

“…The α,β-unsaturated acids have also been prepared from dibromoacetic acid and aldehydes with the aid of an excess amount of SmI 2 . The construction of carbon–carbon double bonds starting from aldehydes has been achieved via Wittig and Horner–Wadsworth–Emmons reactions . However, in both reactions use of a strong base and the formation of a considerable amount of organophosphorous byproducts are unavoidable.…”

Direct Reaction of Dibromoacetic Acid with Aldehydes Promoted by Samarium Diiodide: An Easy, Efficient, and Rapid Synthesis of (E)-α,β-Unsaturated Carboxylic Acids with Total Stereoselectivity†

“…The use of (trimethylsilyl)acetic acid dianion (Peterson olefination) and the cycloaddition of (trimethylsilyl)ketene suffered from a lack of stereoselectivity. No application of the Wittig−Horner reaction with highly enolizable aldehydes has been described, and, in general, this method required fairly stringent conditions to isolate the α,β-unsaturated acids 14b. Finally, the synthesis of α,β-unsaturated carboxylic acids by the reaction of C,O,O -tris(trimethylsilyl)ketene acetal with enolizable aldehydes took place in low yield, and to prepare the starting ketene acetal from (trimethylsilyl)acetic ester, three steps are necessary.…”

Synthesis, applications and Structure-Activity Relationship (SAR) of cinnamic acid derivatives: a review

“…The olefin reaction of (HWE) is a very effective method on the formation of α,β-unsaturated esters. This reaction consists of base-mediated olefination of aldehydes and ketones by ketophosphonates on the formation of CA and CAD's, conforme Esquema 10 ( Sano et al, 2007). Similarly to Wittig reaction, the stereoselective ration E/Z strongly depends on the phosphonate group (Wadsworth & Emmons, 1961;Sano et al, 2007).…”