74531-20-7

Upstream product

• 104-88-1 4-chlorobenzaldehyde 
• 141-05-9 Diethyl maleate 
• 7071-15-0 diethyl 2-(diethoxyphosphoryl)succinate 
• 623-91-6 diethyl Fumarate 

Relevant academic research and scientific papers

One-pot, three-component synthesis of arylidenesuccinates and related compounds

Aromatic and heteroaromatic aldehydes react with diethyl fumarate or diethyl maleate and tri-n-butylphosphlne at room temperature to afford good yields of diethyl arylidenesuccinates. Unsaturated and saturated aldehydes afford cognate products.

Poly(methylhydrosiloxane) as a reductant in the catalytic base-free Wittig reaction

Herein, we report a catalytic, base-free Wittig reaction forming highly functionalized alkenes with PMHS as a terminal reductant and butylacetate as a green solvent. Poly(methylhydrosiloxane) (PMHS) is a non-toxic, enviromentally friendly, inexpensive and easy to handle reductant. However, the inherent low reactivity hampers its applicability in catalytic reactions, such as P(iii)/P(v) redox cycling reactions. Most of these catalytic systems include highly active aryl silanes to facilitate phosphane oxide reduction and are not compatible with PMHS or similar more sustainable terminal reductants. The herein reported catalyst system which is based on a methyl-substituted phosphetane operates at low catalyst loadings without additional co-catalysts and allowes the use of PMHS as terminal reductant. A wide variety of functional groups was tolerated and 25 different alkenes were synthesized in yields up to 96% with excellent stereoselectivity. Mechanistic studies revealed the formation of water from silanol condensation as the main pathway of siloxane formation.

First Base-Free Catalytic Wittig Reaction

The first base-free catalytic Wittig reaction utilizing readily available Bu3P (5 mol %) as an organocatalyst is reported. The initial Michael addition of the phosphine to a suitable acceptor substituted alkene ultimately results in the formation of an ylide which is subsequently converted with an aldehyde. The presented 1H NMR studies actually reveal evidence for the Michael addition and proposed ylide formation. Under the optimized reaction conditions various maleates and fumarates were converted with aromatic, heteroaromatic, and aliphatic aldehydes to evaluate the scope and limitations of this unprecedented reaction. Notably, maleates and fumarates react in a stereoconvergent fashion. The corresponding products were obtained in up to 95% isolated yield and E/Z-selectivities up to 99:1.

Sequential Transformation of Diethyl Phosphite. A Convenient Synthesis of Substituted (E)-3-Alkoxycarbonyl-β,γ-unsaturated Esters

The sequential reaction of diethyl phosphite with sodium alkoxide, dimethyl maleate and aldehydes affords substituted (E)-3-alkoxycarbonyl-β,γ-unsaturated esters in 63-73% yields.

Annelation Reactions of N-Heterocycles to Condensed Pyridones with Bridgehead Nitrogen

The Horner-Wittig reaction of aromatic and heteroaromatic aldehydes with phosphono succinates gives the methylenesuccinates 2a-m and 4a-k in satisfactory yields.The compounds obtained have the E-configuration, as shown by 1H-NMR-spectroscopic and by chemi