81462-45-5

Upstream product

• 80663-30-5 α-chloro-2-vinylstilbene 
• 81462-35-3 (Z)-α-chloro-2-vinylstilbene 
• 2039-88-5 2-bromostyrene 
• 536-74-3 phenylacetylene 
• 6630-33-7 ortho-bromobenzaldehyde 
• 59046-72-9 o-(phenylethynyl)benzaldehyde 
• 2065-66-9 methyl-triphenylphosphonium iodide 

Downstream Products

• 91-20-3 naphthalene 
• 612-94-2 2-phenylnaphthalene 
• 605-02-7 1-phenylnaphthalene 
• 5394-86-5 6-phenyl-1,2-benzofulvene 
• 947395-79-1 acetic acid 2-azido-2-(2-phenyl-ethynyl-phenyl)-ethyl ester 
• 952410-02-5 2-azido-2-(2-(phenylethynyl)phenyl)ethanol 
• 1240389-02-9 C₂₂H₁₆BrNO₂S 
• 1240389-00-7 2-[2-(phenylethynyl)phenyl]-1-tosylaziridine 
• 20669-52-7 3-phenyl-1,2-dihydronaphthalene 

Relevant academic research and scientific papers

Design of leaving groups in radical C-C fragmentations: Through-bond 2c-3e interactions in self-terminating radical cascades

Radical cascades terminated by β-scission of exocyclic C-C bonds allow for the formation of aromatic products. Whereas β-scission is common for weaker bonds, achieving this reactivity for carbon-carbon bonds requires careful design of radical leaving groups. It has now been found that the energetic penalty for breaking a strong σ-bond can be compensated by the gain of aromaticity in the product and by the stabilizing two-center, three-electron "half-bond" present in the radical fragment. Furthermore, through-bond communication of a radical and a lone pair accelerates the fragmentation by selectively stabilizing the transition state. The stereoelectronic design of radical leaving groups leads to a new, convenient route to Sn-functionalized aromatics.

Heavier alkaline earth catalyzed ene-yne cyclizations: Atom-efficient access to tetrahydroisoquinoline frameworks

Tetrahydroisoquinoline frameworks may be accessed with 100% atom efficiency through the alkaline earth catalyzed addition of primary amines to ene-yne substrates through a sequence of intermolecular alkene and intramolecular alkyne hydroamination steps.

ALKENES AS ALKYNE EQUIVALENTS IN RADICAL CASCADES TERMINATED BY FRAGMENTATIONS

Disclosed are methods for rerouting radical cascade cyclizations by using alkenes as alkyne equivalents. The reaction sequence is initiated by a novel 1,2 stannyl shift which achieves chemo- and regioselectivity in the process. The radical “hopping” leads to the formation of the radical center necessary for the sequence of selective cyclizations and fragmentations to follow. In the last step of the cascade, the elimination of a rationally designed radical leaving group via β-C—C bond scission aromatizes the product without the need for external oxidant. The Bu3Sn moiety, which is installed during the reaction sequence, allows further functionalization of the product via facile reactions with electrophiles as well as Stille and Suzuki cross-coupling reactions. This selective radical transformation opens a new approach for the controlled transformation of enynes into extended polycyclic structures of tunable dimensions.

Photochemistry of chloro-2-vinylstilbenes

Short irradiation at 300 nm of α-chloro- and β-chloro-2-vinylstilbene (20 and 21) leads to a mixture of 2-vinyltolane (35) and 2-vinylstilbene (1) accompanied by the cis- and trans-isomers of the starting compounds.Evidence is found for the occurrence of an ionic intermediate during the photolysis of 20 in methanol.At 360 nm, an additional, small amount of 1-chloro-endo- and 1-chloro-exo-6-phenylbenzobicyclohex-2-ene (39) is formed formed from 20.The elimination of hydrogen chloride also occurs during the irradiation of 2-(2-chlorovinyl)stilbene (23) and leads to 2-ethynylstilbene (41).The acetylenic compounds are photocyclized into 2-phenylnaphthalene (38).However, 2-(1-chlorovinyl)stilbene (22) reacts without loss of chlorine to give 1-chloro-exo-5-phenylbenzobicyclo-hex-2-ene (40).This exceptional reaction mode is due to a much higher rate of photocyclization resulting from less distortion in the stilbene moiety and a preference for a conformation better suited to the reaction of the 2-(1-chlorovinyl)stilbene molecule.It is shown that both isomers of 22 can photocyclize into 40.

The Photochemistry of 2-Vinyldiphenylacetylene and Related Compounds

Irradiation of solutions of 2-vinyldiphenylacetylene (5) under anaerobic conditions gives 2-phenylnaphtalene (9) in 90 percent yield.Several derivatives of (5) behave similarly.The reaction is ascribed to the primary formation of a cyclic allene (29), as has been proposed previously for the analogous photocyclization of 1,4-diarylbutenynes into phenylaromatic compounds.The end-product arises from (29) either via a 1,5-hydrogen shift or by addition and elimination of a proton.Irradiation of 2-ethynylstilbene (21) also yields (9), but 1-ethynylphenanthrene (22) is formed as a side-product.