73249-12-4

Upstream product

• 73222-90-9 2-((3-phenylprop-2-yn-1-yl)oxy)phenol 
• 1504-58-1 3-Phenyl-2-propyn-1-ol 
• 100-52-7 benzaldehyde 
• 23970-90-3 (Z)-(2,3-dibromoprop-1-en-1-yl)benzene 
• 120-80-9 benzene-1,2-diol 
• 59106-33-1 (Z)-ethyl 2-bromo-3-phenylprop-2-enoate 
• 2048-31-9 (Z)-2-bromo-3-phenylprop-2-en-1-ol 
• 1794-48-5 1-bromo-3-phenylprop-2-yne 
• 14817-38-0 2‐(prop‐2‐yn‐1‐yloxy)phenol 
• 591-50-4 iodobenzene 
• 104846-76-6 (±)-methyl (1-phenylprop-2-yn-1-yl) carbonate 

Relevant academic research and scientific papers

An easy palladium-catalyzed access to 2-alkylidene-1,4-benzodioxanes

Palladium-catalyzed cyclization of benzene-1,2-diol with various propargylic carbonates led to 2-alkylidene-1,4-benzodioxanes in excellent chemical yields. Diphosphines such as dppb, dpppe or dpph, and monophosphines are the best ligands.

Transition metal-free diastereospecific synthesis of (Z)-2-arylidene-2,3-dihydrobenzo[b][1,4]dioxines by reaction of (Z)-1,2-dibromo-3-aryl-2-propenes with catechols

A transition metal-free, diastereospecific reaction between substituted (Z)-1,2-dibromo-3-phenyl-2-propenes and substituted catechols using Cs2CO3 as a base at 140 °C for 18 h delivers exclusively substituted (Z)-2-arylidene-2,3-dihy

Palladium-catalyzed synthesis of 2,3-dihydro-2-ylidene-1,4-benzodioxins

Palladium-catalyzed condensation of benzene-1,2-diol with various propargylic carbonates, afforded regio- and stereoselectively 2,3-dihydro-2-ylidene-1,4-benzodioxins. The reaction is suggested to proceed by the formation of a (σ-allenyl)palladium complex, followed by the intermolecular attack of the phenoxide ion on this complex to generate a new (σ-allyl)palladium complex in equilibrium with the corresponding (η3-allyl)palladium complex. Intramolecular attack of the phenoxide ion afforded the corresponding benzodioxan compound. This last attack occurs predominantly at the more electrophilic end of the (η3-allyl)palladium intermediate. The Z- or E-stereochemistry of the products was established by 1H NMR and proton NOE measurements and also by X-ray analysis on an example. The Z-stereochemistry generally observed is in agreement with the formation of this (η3-allyl)palladium intermediate. However, in the case of tertiary propargylic carbonates, the E-stereochemistry generally observed could be explained by an intramolecular attack of the phenoxide ion on the intermediate (σ-allyl)palladium complex, in slow equilibrium with the (η3allyl)palladium complex.

Palladium-Catalyzed Heteroannulation Leading to Heterocyclic Structures with Two Heteroatoms: A Highly Convenient and Facile Method for a Totally Regio- and Stereoselective Synthesis of (Z)-2,3-Dihydro-2-(ylidene)-1,4-benzo- and -naphtho [2,3-b]dioxins

A facile method for the synthesis of (Z)-2,3-dihydro-2-(ylidene)-1,4-benzo- and naphthodioxins (3) has been developed using palladium-copper catalysis. Aryl halides 2 were found to react with mono-prop-2-ynylated catechol (la) or 2-hydroxy-3-(prop-2-ynyloxy)naphthalene (Ib) in the presence of (PPh3)2PdCl2 (3.5 mol %) and CuI (7 mol %) in triethylamine by stirring at room temperature for 20 h followed by heating at 100°C for 16 h to give products 3 in good yields. The method is regioand stereoselective and also amenable to bisheteroannulation. The Z-stereochemistry of products 3 was established firmly from 1H NMR, 3JCH values (between vinylic proton and methylenic carbon of the heterocyclic ring), proton NOE measurements, and finally from X-ray analysis. Based on experimental observations and known palladium chemistry, a mechanism has been proposed to explain the regio- and stereoselective product formation. Some of the products 3 were also converted , to 1,4-benzodioxan derivatives 6 using hydrogenation procedure. A uracil derivative of possible biological interest, possessing a 1,4-benzodioxinyl functionality at the C-5 position, has been synthesized.

A totally stereoselective synthesis of (Z)-2-arylidene-1,4-benzodioxanes using palladium-copper catalysis

A convenient and general synthesis of (Z)-2-Arylidene-1,4-benzodioxanes from a mono-prop-2-ynylated catechol and aromatic halides by palladium catalysis is described.