Arylmethyl Bromides Research Articles

Multicomponent reactions (MCRs) of arylmethyl bromides, arylamidines and elemental sulfur toward unsymmetric 3,5-diaryl 1,2,4-thiadiazoles

A base-promoted three-component reaction between arylmethyl bromides, arylamidines and elemental sulfur was developed, leading to unsymmetric 3,5-diaryl-1,2,4-thiadiazoles in moderate to good yields with chemical diversity and complexity. This procedure shows broad substrates scope by employing elemental sulfur and commercially available starting materials under transition-metal free conditions.

Metal-free, visible-light photoredox catalysis: transformation of arylmethyl bromides to alcohols and aldehydes

A mild, simple, and controllable metal-free photocatalytic system for the transformation of arylmethyl bromides to corresponding alcohols and aldehydes in high yields with visible-light irradiation has been achieved. Eosin Y was found to be an efficient promoter for this oxidative dehalogenation reaction under photo irradiation conditions.

ChemInform Abstract: IBX‐Mediated One‐Pot Synthesis of Benzimidazoles from Primary Alcohols and Arylmethyl Bromides.

AbstractThe process is successful for both substrate types in the presence of only 1.1—1.5 equiv.

IBX-mediated one-pot synthesis of benzimidazoles from primary alcohols and arylmethyl bromides

A variety of primary alcohols are shown to be converted to the corresponding benzimidazoles in one pot by employing IBX and o-phenylenediamine in DMSO at room temperature. o-Iodobenzoic acid is the end product of IBX, which is employed in 1.0equiv. Arylmethyl bromides are also shown to be converted likewise to benzimidazoles in moderate yields in one pot, albeit at slightly elevated temperatures.

ChemInform Abstract: Photo‐Ritter Reaction of Arylmethyl Bromides in Acetonitrile.

AbstractAcetamides (III) are formed via photo‐Ritter reaction during irradiation of arylmethyl bromides (I) in MeCN.

Photo-Ritter Reaction of Arylmethyl Bromides in Acetonitrile

The photo-Ritter reaction of five arylmethyl bromides can occur in acetonitrile to give acetamides. The intermediates, carbocations, which are formed from subsequent electron transfer between the radical pairs generated from initial homolytic cleavage of the C–Br bond, are trapped by acetonitrile, and subsequent hydrolysis generates the corresponding acetamides.

Insights into the Role of New Palladium Pincer Complexes as Robust and Recyclable Precatalysts for Suzuki–Miyaura Couplings in Neat Water

AbstractSuzuki–Miyaura biaryl and diarylmethane syntheses via the coupling of arylboronic acids with aryl and arylmethyl bromides are performed in water by means of two new CNC‐type palladium pincer complexes. Good to excellent results (including high TON values and extended recycling procedures) are obtained in most cases for a range of electronically dissimilar halides and boronic acids. On the basis of a series of kinetics studies, transmission electron microscopy (TEM), mercury drop tests, and quantitative poisoning experiments, the real role of the latter palladacycles, closely linked to the formation and active participation of palladium nanoparticles, is discussed.

Highly diastereoselective alkylation of vicinal dianions of chiral succinic acid derivatives: a new general strategy to ( R)-β-arylmethyl-γ-butyrolactones

The vicinal dianions derived from chiral succinic acid derivatives, 1,4-bis[(4 R,5 S)-3,4-dimethyl-2-oxo-5-phenylimidazolidin-1-yl]butane-1,4-dione and 1,4-bis[(4 S,5 R)-3,4-dimethyl-2-oxo-5-phenylimidazolidin-1-yl]butane-1,4-dione react with arylmethyl bromides with high diastereo- and regio-selectivity to provide the corresponding chiral α-arylmethylated succinic acid derivatives; the ( R)-products are converted into ( R)-β-arylmethyl-γ-butyrolactones and ( R)-α-arylmethyl-γ-butyrolactones.

A Novel Preparation of 2‐Naphthyl and 5‐Benzo[B]thienyl Methanesulfonyl Chlorides.

AbstractFor Abstract see ChemInform Abstract in Full Text.

A Novel Preparation of 2-Naphthyl and 5-Benzo[B]thienyl Methanesulfonyl Chlorides

Electron rich arylmethylsulfonyl chlorides can be prepared from arylmethyl bromides by phase transfer sulfonation and chlorination with PCl5.

ChemInform Abstract: Oxidative Transformation of Arylmethyl Bromides and Alcohols with a Combination of Mesoporous Silica FSM‐16 and Alkali Iodides under Photoirradiation.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Oxidative transformation of arylmethyl bromides and alcohols with a combination of mesoporous silica FSM-16 and alkali iodides under photoirradiation.

[reaction: see text]. A mesoporous silica FSM-16 was found to be a selective and recyclable promoter for the oxidative dehalogenation of arylmethyl bromides to provide the corresponding alcohols and for the oxidation of arylmethyl alcohols to provide the corresponding aldehydes with a combination of alkali iodides and solvents under photoirradiation conditions.

Asymmetric alkylation of tert-butyl glycinate Schiff base with chiral quaternary ammonium salt under micellar conditions.

[reaction: see text] The asymmetric alkylation of the tert-butyl glycinate-benzophenone Schiff base 1 with various arylmethyl bromides catalyzed by O-allyl-N-(9-anthracenylmethyl)cinchonidinium bromide (2) proceeded smoothly under micellar conditions (5 equiv of 1 M KOH and 0.4 equiv of Triton X-100) to give the alkylated products in good yields and with good enantioselectivity (72-85% ee), depending on the electrophiles.

ChemInform Abstract: Photooxidation of Arylmethyl Bromides with Mesoporous Silica FSM-16.

A mesoporous silica FSM-16 was found to be a recyclable oxidizing promoter of arylmethyl bromides for the preparation the corresponding carboxylic acids, aldehydes, or ketones under photoirradiation conditions.

Photooxidation of arylmethyl bromides with mesoporous silica FSM-16

A mesoporous silica FSM-16 was found to be a recyclable oxidizing promoter of arylmethyl bromides for the preparation the corresponding carboxylic acids, aldehydes, or ketones under photoirradiation conditions.

Preparation of Intermediates for Fluorinated Lignans by Conjugated and Tandem Additions on 3-Fluorofuran-2(5H)-one

Two syntheses of 3-fluorofuran-2(5H)-one (1) based on Wittig-Horner reaction of ethyl (diethoxyphosphoryl)fluoroacetate (15) with 2-oxoethyl acetate (16) or on transformation of D-erythronolactone (10) are given. 3-Fluorofuran-2(5H)-one (1) and ethyl 2-fluorobut- 2-enoate (2) undergo conjugate addition with soft nucleophiles based on arene- carboxaldehyde dithioacetals 7 to form 2-fluorolactones 3 and 2-fluoroalkanoates 4. Intermediate enolates can be trapped in the sense of tandem addition with arenecarboxaldehydes 8 or (arylmethyl)bromides 9 to form intermediates 5 and 6 for fluorolignans. Although the conjugate addition proceeds with low stereoselectivity yielding mixture of both diastereoisomers, the electrophile in tandem addition attacks the intermediary fluoroenolate exclusively anti to its bulky β-substituent in good accord with non-fluorinated furan- 2(5H)-ones.

ChemInform Abstract: Asymmetric Synthesis. Part 9. Preparation of Chiral α‐Substituted Phenethylamines.

AbstractThe optically active N‐cyanomethyloxazolidine (I) is consecutively alkylated with methyl iodide (II) and the arylmethyl bromides (IV) to yield mixtures of the diastereomers (V).

Debromination of phenacyl and benzylic bromides with tertiary stibine and the mechanistic consideration

Tributylstibine is an efficient reagent for debromination of phenacyl and arylmethyl bromides. The mechanistic difference between stibine and phosphine is discussed briefly.