The place of organocopper reagents in organic synthesis is now well established.' The widespread use of these relatively new reagents is based largely on their ease of preparation and on their ability to effect transformations that are difficult or impossible to accomplish with any other reagents. The organocopper reagents often react in a highly selective fashion: stereoselectively, regioselectively, and chemoselectively. These characteristics are important, especially in the construction of complex organic molecules. Perhaps the most noteworthy example of the use of organocopper reagents in complex organic synthesis involves preparation of the E series of prostaglandins.2 Although they have been used effectively and broadly during the past 10 years, organocopper reagents still pose structural and mechanistic problems; their thermal and air instability preclude their easy isolation, and their aggregation and ability to exist as mixed-valence clusters complicates mechanistic investigations. Ketones are central to organic chemistry, because they can be converted to many other functional groups and because they can be used for attachment of other carbon units. Due to this key role of ketones, organocopper reagents have been applied to synthesis of ketones from carboxylic acid chloride^,^ a-haloketones," and a$-unsaturated ketones.' Addition of organocopper reagents to a$-ethylenic ketones leads regiospecifically to intermediates that can react with some electrophiles (R'X) to form a$-disubstituted ketones5 (SCHEME 1). Some examples of natural products that are a$-dialkyl ketones are shown in SCHEME 2. Synthesis of the valerane class of sesquiterpenes is difficult because of presence of two quaternary carbon centers at the ring fusion positions and because of the stereochemical relationship between the angular methyl groups and the pendant isopropyl group. Several possible organocopper B-addition/a-alkylation 0

AbstractAlkyllithium‐Verbindungen (II) addieren an tert.‐Butoxy‐Cu(I)‐alkoholat (I) zu den Alkylierungsmitteln (III), die mit Alkylhalogeniden (IV) zu den "Dimeren" (V), mit Cyclohexenon (VI) zum Addukt (VII) und mit Säurechloriden (VIII) zu Ketonen (IX) reagieren.

Chemischer Informationsdienst. Organische ChemieVolume 2, Issue 5 Isocyclic Compounds ChemInform Abstract: METHYL- UND N-ALKYLKETONE AUS CARBONSAEURECHLORIDEN UND ORGANISCHEN KUPFERREAGENTIEN G. H. POSNER, G. H. POSNERSearch for more papers by this authorC. E. WHITTEN, C. E. WHITTENSearch for more papers by this author G. H. POSNER, G. H. POSNERSearch for more papers by this authorC. E. WHITTEN, C. E. WHITTENSearch for more papers by this author First published: February 2, 1971 https://doi.org/10.1002/chin.197105237Read 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. Volume2, Issue5February 2, 1971 RelatedInformation

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOrganometallic Polymers. IX. Polyesters of 1,1'-Bis(chlorocarbonyl)cobalticinium HexafluorophosphateC. U. Pittman Jr., O. E. Ayers, S. P. McManus, J. E. Sheats, and C. E. WhittenCite this: Macromolecules 1971, 4, 3, 360–362Publication Date (Print):May 1, 1971Publication History Published online1 May 2002Published inissue 1 May 1971https://doi.org/10.1021/ma60021a025Request reuse permissions Article Views133Altmetric-Citations31LEARN 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 (354 KB) Get e-Alertsclose Get e-Alerts