27764-13-2

Upstream product

• 345-35-7 2-fluorobenzyl chloride 
• 446-52-6 2-Fluorobenzaldehyde 
• 106795-58-8 (o-fluorobenzyl)triphenylphosphonium chloride 
• 63909-54-6 2-fluoro-1-diethylphosphonomethyl-benzene 

Relevant academic research and scientific papers

Tert-butyl phenyl sulfoxide: A traceless sulfenate anion precatalyst

tert-Butyl phenyl sulfoxide is employed as a traceless precatalyst for the generation of sulfenate anions under basic conditions and has been used to catalyze the coupling of benzyl halides to trans-stilbenes. The advantage of this precatalyst over previous precatalysts is that the byproduct generated on catalyst formation is a gas, facilitating product isolation in high purity. Using this second generation catalyst, a variety of trans-stilbenes were generated in 39-98% isolated yield.

Unusual Fusion of α-Fluorinated Benzophenones under McMurry Reaction Conditions

By exposure of α-fluorinated benzophenones to McMurry reaction conditions, we have observed the remarkable formation of 9,10-diphenylanthracene derivatives. This unexpected transformation necessitates the cleavage of the exceptionally stable aromatic C?F bond under mild McMurry conditions. In this work, the condensation of several related fluorinated benzo- and acetophenones has been investigated, which allow us to propose a domino-like fusion mechanism for this unusual transformation. The scope and limitations of the fluorine-promoted benzophenone fusion are subsequently discussed.

Selenolate Anion as an Organocatalyst: Reactions and Mechanistic Studies

A new organocatalyst, the selenolate anion [RSe]–, generated from bench-stable and commercially available diphenyl diselenide or from phenyl benzyl selenide (10 mol%) is introduced. Benchmarking is performed in the conversion of benzylic chlorides into trans-stilbenes selectively at room temperature. Mechanistic studies support the intermediacy of the selenolate anion and of 1,2-diphenylethyl phenyl selenide. (Figure presented.).

Activation of anti-oxidant Nrf2 signaling by substituted trans stilbenes

Nrf2, which is a member of the cap'n’ collar family of transcription factors, is a major regulator of phase II detoxification and anti-oxidant genes as well as anti-inflammatory and neuroprotective genes. The importance of inflammation and oxidative stress in many chronic diseases supports the concept that activation of anti-oxidant Nrf2 signaling may have therapeutic potential. A number of Nrf2 activators have entered into clinical trials. Nrf2 exists in the cytosol in complex with its binding partner Keap1, which is a thiol-rich redox-sensing protein. In response to oxidative and electrophilic stress, select cysteine residues of Keap1 are modified, which locks Keap1 in the Nrf2-Keap1 complex and allows newly synthesized Nrf2 to enter the nucleus. Numerous Nrf2-activating chemicals, including a number of natural products, are electrophiles that modify Keap1, often by Michael addition, leading to activation of Nrf2. One concern with the design of Nrf2 activators that are electrophilic covalent modifiers of Keap1 is the issue of selectivity. In the present study, substituted trans stilbenes were identified as activators of Nrf2. These activators of Nrf2 are not highly electrophilic and therefore are unlikely to activate Nrf2 through covalent modification of Keap1. Dose-response studies demonstrated that a range of substituents on either ring of the trans stilbenes, especially fluorine and methoxy substituents, influenced not only the sensitivity to activation, reflected in EC50values, but also the extent of activation, which suggests that multiple mechanisms are involved in the activation of Nrf2. The stilbene backbone appears to be a privileged scaffold for development of a new class of Nrf2 activators.

Photocyclodehydrofluorination

Mallory-type photocyclization involves a series of photoreactions of stilbenes, o-terphenyls and related derivatives, which undergo intramolecular cyclization via dihydrophenanthrene intermediates. In typical Mallory photocyclizations, oxidants are usually needed to produce the final phenanthrene-containing product. In the research described here, appropriately fluorinated stilbenes and o-terphenyls undergo ring closure and HF is eliminated. This photocyclodehydrofluorination (PCDHF) reaction is very useful to produce a wide range of selectively fluorinated polynuclear aromatic hydrocarbons that possess a phenanthrene (or heterocyclic analogue of phenanthrene) substructure. These fluorinated products are of great interest in various aspects of the materials science.

A new role for sulfenate anions: Organocatalysis

(Chemical Equation Presented) The sulfenate anion is introduced for the first time as a catalyst and was found to facilitate the conversion of benzyl halides to trans-stilbenes. CPME=Cyclopentyl methyl ether.

A new class of organocatalysts: Sulfenate anions

Sulfenate anions are known to act as highly reactive species in the organic arena. Now they premiere as organocatalysts. Proof of concept is offered by the sulfoxide/sulfenate-catalyzed (1-10 mol%) coupling of benzyl halides in the presence of base to generate trans-stilbenes in good to excellent yields (up to 99%). Mechanistic studies support the intermediacy of sulfenate anions, and the deprotonated sulfoxide was determined to be the resting state of the catalyst. Sulfenates take center stage: Sulfenate anions are known as highly reactive species in the organic arena. Now they premiere as organocatalysts: A sulfoxide/sulfenate (1-10 mol%) promotes the transformation of benzyl halides into trans-stilbenes under basic conditions (up to 99% yield). CPME=cyclopentyl methyl ether.

Sodium sulfinate-mediated trans-stilbene formation from benzylic halides

A convenient and efficient method for the synthesis of various symmetrical and non-symmetrical trans-stilbene derivatives from benzylic halides in the absence of any transition metals is described. Sodium sulfinates played an important role in this transformation. Various functional groups were well tolerated under the optimized reaction conditions. Copyright

A convenient and mild chromatography-free method for the purification of the products of Wittig and Appel reactions

A mild method for the facile removal of phosphine oxide from the crude products of Wittig and Appel reactions is described. Work-up with oxalyl chloride to generate insoluble chlorophosphonium salt (CPS) yields phosphorus-free products for a wide variety of these reactions. The CPS product can be further converted into phosphine.

Reductive olefination of aldehydes via chromium brook rearrangement

The combination of CrCl2 and silyl chlorides converts aryl and conjugated aldehydes into olefinic adducts in good to excellent yields. When constrained by structural features, the intermediate vic-diol can be isolated. Available data are consistent with a novel chromium Brook rearrangement.