66527-92-2

Upstream product

• 4628-21-1 (Z)-1-chloro-2-butene 
• 108-95-2 phenol 
• 13610-09-8 but-2-ynyloxybenzene 
• 563-52-0 2-chloro-3-butene 
• 4894-61-5 trans-but-2-enyl chloride 
• 4784-77-4 (E)-1-Bromo-2-butene 

Downstream Products

• 4050-45-7 trans-2-hexene 
• 935-00-2 trans-4-phenyl-2-butene 
• 18272-63-4 2-(but-3-en-2-yl)phenol 

Relevant academic research and scientific papers

Ruthenium-catalyzed o-allylation of phenols from allylic chlorides via cationic [Cp*(η3-allyl)(MeCN)RuX][PF6] complexes

The [Cp*(MeCN)3Ru(II)][PF6] complex is an efficient catalyst precursor for the O-allylation of phenols with allylic chlorides in the presence of K2CO3 under mild conditions. This ruthenium precursor affords branched allyl aryl ethers according to a regioselective reaction, which contrasts with the uncatalyzed nucleophilic substitution from the same substrates. Stable (η3-allyl)Ru(IV) cationic complexes resulting from the reaction of [Cp*(MeCN) 3Ru][PF6] with allylic halides were identified as intermediate catalytic species. An X-ray structure determination of the complex [Cp*(MeCHCHCH2)(MeCN)RuBr] [PF6] disclosed an (endo-trans-MeCHCHCH2) allylic ligand. The structural information obtained from the study of Cp*(allyl)Ru(IV) complexes indicated that electronic effects at the coordinated allylic ligand likely account for the better regioselectivity obtained from cinnamyl chloride as compared to aliphatic allylic chlorides.

cis-Selective Transfer Semihydrogenation of Alkynes by Merging Visible-Light Catalysis with Cobalt Catalysis

Herein, the first example of visible-light-driven, cobalt-catalyzed transfer semihydrogenation of alkynes to alkenes is reported. It is carried out by using Ir[dF(CF3)ppy]2(dtbbpy)]PF6 as photosensitizer, CoBr2/n-Bu3P as proton-reducing catalyst, and i-Pr2NEt/AcOH as the hydrogen source. Under the established catalytic system, the semihydrogenation proceeds with Z as the major selectivity and with inhibition of over-reduction. Under mild reaction conditions, both internal and terminal alkynes, as well as reducible functional groups such as halogen, cyano, and ester, are tolerated. Preliminary mechanistic studies revealed the dual role of the photosensitizer in initiating the reaction via a single-electron transfer process and controlling the stereoselectivity via an energy transfer process. (Figure presented.).

Regioselective Wacker-Type Oxidation of Internal Olefins in tBuOH Using Oxygen as the Sole Oxidant and tBuONO as the Organic Redox Cocatalyst

A regioselective Wacker-Tsuji oxidation of internal olefins in tBuOH has been developed using oxygen as the terminal oxidant and tert-butyl nitrite as the simple organic redox cocatalyst without the involvement of hazardous cocatalysts or harsh reaction conditions. A series of internal olefins bearing various functional groups can be oxidized to the corresponding substituted ketones in generally good yields with high regioselectivities.

Stereodivergent Alkyne Reduction by using Water as the Hydrogen Source

A homogeneous Pd-catalyzed stereodivergent reduction of alkynes to Z and E alkenes by using H2O as the H2 source is presented. Mediated by a diboron reagent, the transfer hydrogenation has been accomplished to yield the desired geometrical isomer by rational ligand selection. The switchable stereoselectivity achieved using simple phosphine ligands is generally excellent. D2O has also been used as a D2 source for synthesizing the corresponding deuterated olefins. Supported by a gram-scale synthesis, the reaction can easily be scaled up making it an efficient way to prepare alkenes commercially as well. Mechanistic studies suggest formation of H?PdL2?OAc as the crucial step leading to the presence of two pathways involving H?Pd?B(OR)2 and molecular H2 as active intermediates.

Tert-Butyl Nitrite: Organic Redox Cocatalyst for Aerobic Aldehyde-Selective Wacker-Tsuji Oxidation

An aldehyde-selective aerobic Wacker-Tsuji oxidation is developed. Using tert-butyl nitrite as a simple organic redox cocatalyst instead of copper or silver salts, a variety of aldehydes were achieved as major products in up to 30/1 regioselectivity as well as good to high yields at room temperature.

Tandem Claisen Rearrangement/6-endo Cyclization Approach to Allylated and Prenylated Chromones

Allyl, dimethylallyl and prenyl ethers derived from o-acylphenols reacted upon microwave irradiation to form C-allylated or -prenylated chromone derivatives, depending on the substitution pattern of the arene and the allyl substituent. The reaction proceeds through a tandem Claisen rearrangement and 6-endo-trig or 6-endo-dig cyclization sequence. For prenyl ethers, the tandem sequence can be extended by a Cope rearrangement to furnish 6-prenylchromones. The method is potentially useful for the synthesis of natural products and drugs.

Alteration of relative affinities toward myocardial and vascular β adrenoceptors induced by side-chain substitution of aryloxypropanolamines1

Several conformationally defined aryloxypropanolamines of the type ArOCH2CH(OH)CH(R)NHR1 have been synthesized and tested in vivo for β-adrenoceptor blockade. Key intermediates in the syntheses were the appropriate cis- and trans-disubstituted olefins. Epoxidation of the olefins, followed by amination of the resulting cis- and trans-epoxides, yielded the desired diastereomeric model compounds with a defined threo and erythro stereochemistry, respectively. All active compounds in this series exhibit a simple, bimolecular, competitive antagonism at β adrenoceptors. Proper substitutions of the alkanolamine side chain result in vascular selective or cardioselective β-adrenoceptor antagonists, probably as a consequence of the sterically altered ability to interact with β1 and β2 adrenoceptors. dl-erythro-1-Phenoxy-3-[3,4-dimethoxyphenethyl)amino] butan-2-ol is a cardioselective β-adrenoceptor antagonist with a selectivity ratio significantly higher than that of practolol (β1/β2>40 vs. β1/β2=22) but of equal potency (pA2 values = 6.66 and 6.64, respectively). Phenyl substitution at C-3 of the alkanolamine side chain drastically reduces affinity to both types of β adrenoceptors (pA25.0), thus representing a cutoff point. It is concluded that steric factors, as manifested by bulk tolerance at various parts of the aryloxypropanolamine side chain, are major determinants of affinity toward β-adrenoceptor subtypes. β-Adrenoceptor blockade is unrelated to the lipophilic character of the test compounds.