01945nas a2200205   4500008004100000022001400041245008700055210006900142260007500211300001400286520114800300653002301448653001701471653005501488653002101543653002501564100001701589700001901606856011401625       2005                        eng d  a0039-788100aConcise account of recent S(N)2 ` grignard coupling reactions in organic synthesis0 aConcise account of recent SN2 grignard coupling reactions in org  aRUDIGERSTR 14, D-70469 STUTTGART, GERMANYbGEORG THIEME VERLAG KGcNOV  a2995-30223 a<p>Over the past few decades studies oil controlling the chemo-, regio- and stereoselectivities of allylic Substitution reactions have been well documented in the literature and the S(N)2' Grignard coupling reaction has emerged as a very powerful tool ill selective carbon-carbon bond formation. This review focuses on all the recent synthetic developments in this special class of reactions. 1 Introduction 2 S(N)2' Grignard Coupling Reactions with Allylic Substrates 2.1 Allyl Halides 2.2 Allyl Acetates 2.3 Allyl Carbonates 2.4 Allyl Carbamates 2.5 Allyl Ethers 2.6 Allyl Silyl Ethers 2.7 Allyl Epoxides 2.8 Allyl Aziridines 2.9 Allyl Oxazolidinones 2.10 Allyl Thioethers 2.11 Allyl Benzotriazoles 2.12 Oxabicyclic Alkenes 2.13 Azabicyclic Alkenes 2.14 Oxa-azabicyclic Alkenes 3 S(N)2' Grignard Coupling Reactions with Propargyl Substrates 3.1 Propargyl Acetates 3.2 Propargyl Silyl Ethers 3.3 Propargyl Epoxides 3.4 Propargyl Aziridines 3.5 Propargyl Dithioacetals 3.6 Propargyl Thioethers 4 S(N)2' Grignard Coupling Reactions with Bromoallenes 5 S(N)2' Grignard Coupling Reactions in Natural/Unnatural Product Synthesis 6 Conclusions.</p>10aallylic substrates10abromoallenes10achiral/achiral S(N)2 ` Grignard coupling reactions10aNatural products10apropargyl Substrates1 aKar, Anirban1 aArgade, N., P.  uhttps://library.ncl.res.in/content/concise-account-recent-sn2-grignard-coupling-reactions-organic-synthesis-001012nas a2200217   4500008004100000022001400041245003600055210003600091260007500127300001400202520033400216653002900550653002200579653002200601653002900623653001600652653002000668100001700688700001900705856007000724       2005                        eng d  a0039-788100aFacile synthesis of rubrolide E0 aFacile synthesis of rubrolide E  aRUDIGERSTR 14, D-70469 STUTTGART, GERMANYbGEORG THIEME VERLAG KGcSEP  a2284-22863 a<p>A simple and efficient synthesis of rubrolide E (1e) has been demonstrated via Meerwein coupling reaction of para-anisyl-diazonium chloride with N-phenylmaleimide (2), regioselective reduction of para-anisylmaleic anhydride (4), Knoevenagel condensation of butyrolactone 5 with para-anisaldehyde and demethylation pathway.</p>10aKnoevenagel condensation10aMeerwein coupling10aN-phenylmaleimide10aregioselective reduction10arubrolide E10aTotal synthesis1 aKar, Anirban1 aArgade, N., P.  uhttps://library.ncl.res.in/content/facile-synthesis-rubrolide-e-000924nas a2200217   4500008004100000022001400041245004100055210003500096260007500131300001400206520023700220653003100457653003700488653002100525653001800546653002700564653001000591100001700601700001900618856006900637       2005                        eng d  a0039-788100aSimple synthesis of (+/-)-sarkomycin0 aSimple synthesis of sarkomycin  aRUDIGERSTR 14, D-70469 STUTTGART, GERMANYbGEORG THIEME VERLAG KGcMAY  a1234-12363 a<p>A facile 6-step route to (+/-)-sarkomycin in 17% overall yield has been described via Michael addition of nitromethane to 2-hydroxymethyl-2-cyclopentenone, oxone-induced oxidative Nef reaction, and acid catalyzed dehydration.</p>10a(+/-)-sarkomycin synthesis10a2-hydroxymethyl-2-cyclopentenone10aMichael addition10anitromethane.10aoxidative Nef reaction10aOxone1 aKar, Anirban1 aArgade, N., P.  uhttps://library.ncl.res.in/content/simple-synthesis-sarkomycin-002123nas a2200253   4500008004100000022001400041245009900055210006900154260010600223300001400329490000700343520116100350653003301511653003601544653002201580653002101602653001701623653003101640653001401671100001701685700001801702700001901720856013001739       2005                        eng d  a0040-402000aSynthesis of naturally occurring bioactive butyrolactones: maculalactones A-C and nostoclide I0 aSynthesis of naturally occurring bioactive butyrolactones macula  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcMAY  a5297-53020 v613 a<p>Starting from citraconic anhydride (13), a simple multistep (9-10 steps) synthesis of naturally occurring butyrolactones maculalactone A (3), maculalactone B (1), maculalactone C (2) and nostoclide 1 (4) have been described with good overall yields via dibenzylmaleic anhydride (20) and benzylisopropylmaleic anhydride (27). The two anhydrides 20 and 27 were prepared by S(N)2' coupling reactions of appropriate Grignard reagents with dimethyl bromomethylfumarate (14), LiOH-induced hydrolysis of esters to acids, bromination of carbon-carbon double bond, in situ dehydration followed by dehydrobromination and chemoselective allylic substitution of bromoatom in disubstituted anhydrides 19 and 26 with appropriate Grignard reagents. The NaBH4 reduction of these anhydrides 20 and 27 furnished the desired lactones 21 and 29, respectively. The lactone 21 on Knoevenagel condensation with benzaldehyde, furnished maculalactone B (1), which on isomerization gave maculalactone C (2). Selective catalytic hydrogenation of 1 gave maculalactone A (3). The conversion of lactone 29 to nostoclide 1 (4) is known. (c) 2005 Elsevier Ltd. All rights reserved.</p>10adimethyl bromomethylfumarate10adisubstituted maleic anhydrides10amaculalactone A-C10aNaBH4 reductions10anostoclide 110aS(N)2 ` Grignard couplings10asynthesis1 aKar, Anirban1 aGogoi, Sanjib1 aArgade, N., P.  uhttps://library.ncl.res.in/content/synthesis-naturally-occurring-bioactive-butyrolactones-maculalactones-c-and-nostoclide-i-0