Reaction Of Organoboranes Research Articles

Synthesis of Symmetrical Ketones from Organoboranes and 4,4-Dimethyl-2-oxazoline

Abstract Organoboranes readily obtainable by the hydroboration of alkenes have been recently recognized as highly valuable reagents and intermediates for the synthesis of organic compounds with various functional groups.1 However, until most recently, there have been no successful reports on the direct synthesis of carboxylic acids from organoboranes.2 Since 1967, we have made continuous efforts to discover such a conversion, as one of which we examined the reaction of organoboranes with the lithium salt of 4,4-dimethyl-2-oxazoline followed by treatment with methyl iodide and alkaline hydrogen peroxide, based on the following working hypothesis. Organoboranes may react with the lithium salt of 4,4-dimethyl-2-oxazoline3 to yield the organoborate (I), which are then treated with methyliodide to afford the boron derivatives (11). Finally the organoboranes (11) are changed to the corresponding carboxylic acids by the usual a1kaline hydrogen peroxideoxidation and subsequent acidification (Eq. 1). The actually 05 tained products, however, were not the expected carboxylic acids, and we found that symmetrical ketones are prepared in moderate yiels, when organoboranes with primary alkyl groups are used.

SYNTHESIS OF ARYL HALIDESviaORGANOBORANE CHEMISTRY

A method for the rapid synthesis of a variety of substituted aryl halides by the reaction of organoboranes with halide ions in the presence of chloramine-T is described in detail. The products were purified by column chromatography on silica gel using a mixture of petroleum ether-ethyl acetate as eluent.

ChemInform Abstract: A Novel Synthesis of Symmetrie Ketones by the Reaction of Organoboranes with Catechol Dichloromethylene Ether in the Presence of Methyllithium.

AbstractDie Umsetzung der Trialkylborane (II) mit der Dichlorverbindung (I) und Methyllithium und anschließende Oxidation mit alkalischen H2O2 führt zu den symmetrischen Ketonen (III).

Fast, mild, and convenient procedures for iodination and bromination of carbohydrates: reactions of organoboranes with iodine monochloride, sodium iodide, bromine, and bromine chloride

5,6-Dideoxy-1,2-O-isopropylidene-3-O-methanesulfonyl-α-D-xlyo-hexofuranosene-5 (1), reacts with BH3–THF to form the tris(glycosyl)borane (2) and with dicyclohexylborane to form the dicyclohexylglycosylborane (3). The iodination and bromination of 2 and 3 has been investigated using a variety of electrophiles. Iodination of either 2 or 3 with NaI–Chloramine-T/NaOAc is complete within one minute with high percentage uptake of iodine (70–90%) and recovery of the iodinated sugar (4). Bromination of 2 in 15 minutes with NaBr–Chloramine-T permits a high percentage uptake of bromine (75%), and bromination of 3 in 15 minutes with Br2/NaOAc gives the brominated sugar (5) with a reasonably good yield (60%) with respect to the starting material (1).

Metal carbonyl catalysis of organoborane reactions. Cobalt carbonyl catalyzed reductive carbonylation of Schiff bases

Metal carbonyl catalysis of organoborane reactions. Cobalt carbonyl catalyzed reductive carbonylation of Schiff bases

Synthesis of nitrogen-15-labelled primary amines via organoborane reactions

15 N-Labelled primary amines are readily snythesized via the reaction of organoboranes with 15N-enriched ammonium hydroxide; functionally substituted organic amines are efficently prepared via the new synthesis.

A Novel Synthesis of Symmetric Ketones by the Reaction of Organoboranes with Catechol Dichloromethylene Ether in the Presence of Methyllithium

A Novel Synthesis of Symmetric Ketones by the Reaction of Organoboranes with Catechol Dichloromethylene Ether in the Presence of Methyllithium

Synthesis of carbon-13 labelled carboxylic acids via organoborane reactions

13 C-Labelled carboxylic acids are readily synthesized via the reaction of organoboranes with 13C-enriched carbon monoxide; functionally substituted acids are efficiently prepared via a carbonylation–oxidation sequence.

Reaction of Organoboranes with iodine

Abstract The reaction of organoboranes with iodine is an efficient method for synthesizing alkyl iodides.1–3 Unfortunately the earlier methods employed sodium methoxide as a reactant which is a potential problem when the organoborane contians reactive functional groups. We recently reported that organoboranes readily react with iodine monochloride in the presence of sodium acetate, a mild base.4,5.

Convenient synthesis of alkyl amines via the reaction of organoboranes with ammonium hydroxide

A process for the preparation of alkyl amines in which the reagents are generated in situ under mild and convenient reaction conditions is described. An organoborane is prepared via hydroboration, aqueous ammonium hydroxide is added, and then aqueous sodium hypochlorite is added to the mixture. Two of the alkyl groups in the trialkylborane are converted to the corresponding amines in good yield. (BLM)

Facile conversion of alkenes into alkyl bromides via reaction of organoboranes with bromine or bromine chloride

Facile conversion of alkenes into alkyl bromides via reaction of organoboranes with bromine or bromine chloride

Syntheses of organic iodides via reaction of organoboranes with sodium iodide

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSyntheses of organic iodides via reaction of organoboranes with sodium iodideGeorge W. Kabalka and E. Eugene GoochCite this: J. Org. Chem. 1981, 46, 12, 2582–2584Publication Date (Print):June 1, 1981Publication History Published online1 May 2002Published inissue 1 June 1981https://doi.org/10.1021/jo00325a030RIGHTS & PERMISSIONSArticle Views720Altmetric-Citations57LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (417 KB) Get e-Alerts Get e-Alerts

The Reaction of Organoboranes with Ethyl P-Nitrobenzenesulfonoxy-Carbamate Under Two-Phase Conditions. A Convenient Synthesis of Ethyl N-Alkylcarbamates from Olefins via Hydroboration

Abstract Organoboranes readily obtainable from olefins via hydroboration have been shown to be versatile synthetic reagents and intermediates.1 Many reports have appeared dealing with the syntheses of primary,2 secondary,3 and tertiary4 amines from organoboranes. On the other hand, there are a few examples of the similar reactions leading to nitrogen compounds possessing substituents other than hydrogen or alkyl groups attached to nitrogen. It was known that the reaction of organoboranes with iron(III) azide in the presence of hydrogen peroxide gives corresponding azidoalkanes,5 and N-alkylsulfonamides6 are prepared via the reaction of organoboranes with chloramine-T and its analogues.

New method for radioiodinating organic compounds via organoborane reactions

The use of organoboranes in the syntheses of radioiodine labelled materials offers a convenient and mild alternative to traditional methods; iodine-125 labelled materials have been synthesized in good radio-chemical yields, and the methoid is suitable for no-carrier-added isotope incorporation.

The preparation of α-hydroxyorganosilanes from α-borylorganosilane intermediates [1

The generation of α-silyl-α-borylmethane derivatives as intermediates and their oxidation to α-hydroxyorganosilanes is reported. The formation of the intermediate α-silyl-α-borylmethane derivatives is via the type I transfer reaction of organoboranes with either (trimethylsilyl)bromomethyllithium and (phenyldimethylsilyl)chloromethyllithium in THF or in some cases hexane.

Remarkable countercation effect in the reaction of organoboranes with enolates

1H and 11B NMR evidence that, whereas lithium enolates derived from ketones do not detectably interact with triorganoboranes, the corresponding potassium enolates react with relatively unhindered triorganoboranes to form potassium enoxyborates often without any indication of dissociation is presented.

The Reaction of (Phenyldimethylsilyl)dichloromethyllithium with Organoboranes. A Synthesis of α-Hydroxyorganosilanes and Ketones

Abstract The α-transfer reaction of organoboranes has been utilized to great advantage in the employment of organoboranes in synthesis.2 We report here that this process can be used as illustrated in eq 1 to generate α-hydroxyorganosilanes, which can be converted to ketones. This procedure serves to incorporate two of the groups of the organoborane into the product as well as generating the hydroxyl group via oxidation of the newly formed carbon-boron bond.

ChemInform Abstract: REACTIONS OF ORGANOBORANES AND 2‐LITHIO‐2‐ALKYL‐1,3‐BENZODITHIOLES. A NEW, IMPROVED SYNTHESIS OF KETONES

Chemischer InformationsdienstVolume 10, Issue 38 Preparative Organic Chemistry ChemInform Abstract: REACTIONS OF ORGANOBORANES AND 2-LITHIO-2-ALKYL-1,3-BENZODITHIOLES. A NEW, IMPROVED SYNTHESIS OF KETONES S. NCUBE, S. NCUBESearch for more papers by this authorA. PELTER, A. PELTERSearch for more papers by this authorK. SMITH, K. SMITHSearch for more papers by this author S. NCUBE, S. NCUBESearch for more papers by this authorA. PELTER, A. PELTERSearch for more papers by this authorK. SMITH, K. SMITHSearch for more papers by this author First published: September 18, 1979 https://doi.org/10.1002/chin.197938174Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume10, Issue38September 18, 1979 RelatedInformation

Reactions of organoboranes and 2-lithio-2-alkyl-1,3-benzodithioles. A new, improved synthesis of ketones

Reactions of trialkylboranes with 2-lithio-2-alkyl-1,3-benzodithioles followed by oxidation give ketones in good yields. This method is far less subject to steric hindrance than the analogous reactions using anions derived from bis(phenylthio)alkanes.

Improved synthesis of tertiary alcohols from reactions of organoboranes with 2-lithio-1,3-benzodithioles

Treatment of trialkylboranes with 2-lithio-1,3-benzodithioles and then mercuric chloride (or methyl fluorosulhonate) followed by oxidation gives tertiary alcohols in high yields. The method is applicable to reactions of hindered organoboranes that fail using 1-lithio-1,1-bis(phenylthio)alkanes.