Danishefsky's diene (Kitahara diene) is an organosilicon compound and a diene with the formal name ''trans''-1-methoxy-3-trimethylsilyloxy-buta-1,3-diene named after

Samuel J. Danishefsky Samuel J. Danishefsky (born March 10, 1936) is an American chemist working as a professor at both Columbia University and the Memorial Sloan-Kettering Cancer Center in New York City. Birth and education Samuel J. Danishefsky was born in 1936 in ...

. Because the diene is very electron-rich it is a very reactive

reagent In chemistry, a reagent ( ) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. The terms ''reactant'' and ''reagent'' are often used interchangeably, but reactant specifies a ...

in Diels-Alder reactions. This diene reacts rapidly with electrophilic alkenes, such as maleic anhydride. The methoxy group promotes highly regioselective additions. The diene is known to react with amines, aldehydes, alkenes and alkynes. Reactions with imines and nitro-olefins have been reported. It was first synthesized by the reaction of trimethylsilyl chloride with ''4-methoxy-3-buten-2-one'' and zinc chloride: Danishefskys diene application2

The diene has two features of interest: the substituents promote regiospecific addition to unsymmetrical dienophiles and the resulting adduct is amenable to further functional group manipulations after the addition reaction. High regioselectivity is obtained with unsymmetrical alkenes with a preference for a 1,2-relation of the ether group with the electron-deficient alkene-carbon. All this is exemplified in this

aza Diels-Alder reaction Aza or AZA may refer to: Places *Aza, Azerbaijan, a village and municipality *Azadkənd, Nakhchivan or Lower Aza, Azerbaijan *Aza, medieval name of Haza, Province of Burgos, Spain *Aźa, a Tibetan name for the Tuyuhun kingdom *Aza, a Hebrew romani ...

In the cycloaddition product, the

silyl ether Silyl ethers are a group of chemical compounds which contain a silicon atom covalently bonded to an alkoxy group. The general structure is R1R2R3Si−O−R4 where R4 is an alkyl group or an aryl group. Silyl ethers are usually used as protecting g ...

is a synthon for a carbonyl group through the enol. The methoxy group is susceptible to an elimination reaction enabling the formation of a new alkene group. Applications in

asymmetric synthesis Enantioselective synthesis, also called asymmetric synthesis, is a form of chemical synthesis. It is defined by IUPAC as "a chemical reaction (or reaction sequence) in which one or more new elements of chirality are formed in a substrate molecul ...

have been reported. Derivatives have been reported.

References

{{Reflist, 4, refs=

; Kitahara, T. Useful diene for the Diels-Alder reaction. J. Am. Chem. Soc. 1974, 96, 7807-7808. {{doi, 10.1021/ja00832a031 ''Strategic Applications of Named Reactions in Organic Synthesis'', Laszlo Kurti,Barbara Czako, Elsevier 2005 Preparation and Diels-Alder Reaction of a Highly Nucleophilic Diene. Org. Synth., Coll. Vol. 7, p.312 (1990); Vol. 61, p.147 (1983)
Link
/ref>''Asymmetric aza-Diels-Alder reaction of Danishefsky's diene with imines in a chiral reaction medium'' Pegot B, Nguyen Van Buu O, Gori D, Vo-Thanh G Beilstein Journal of Organic Chemistry, 2006''
Link
{{webarchive, url=https://web.archive.org/web/20061011224545/http://bjoc.beilstein-journals.org/content/pdf/1860-5397-2-18.pdf , date=2006-10-11 This is an

asymmetric reaction Enantioselective synthesis, also called asymmetric synthesis, is a form of chemical synthesis. It is defined by IUPAC as "a chemical reaction (or reaction sequence) in which one or more new elements of chirality are formed in a substrate molecu ...

with a chiral ionic liquid as

chiral solvent Chirality is a property of asymmetry important in several branches of science. The word ''chirality'' is derived from the Greek (''kheir''), "hand", a familiar chiral object. An object or a system is ''chiral'' if it is distinguishable from ...

. The reported

chemical yield In chemistry, yield, also referred to as reaction yield, is a measure of the quantity of moles of a product formed in relation to the reactant consumed, obtained in a chemical reaction, usually expressed as a percentage. Yield is one of the pri ...

is 66% with 60% diastereomeric excess ''Asymmetric hetero Diels-Alder reactions of Danishefsky's diene and glyoxylate esters catalyzed by chiral bisoxazoline derived catalysts'' Arun K. Ghosh, Packiarajan Mathivanan, John Cappiello, K. Krishnan Tetrahedron: Asymmetry Volume 7, Issue 8, August 1996, Pages 2165–2168 {{doi, 10.1016/0957-4166(96)00261-3 ''Acid-Free Aza Diels−Alder Reaction of Danishefsky's Diene with Imines'' Yu Yuan, Xin Li, and Kuiling Ding: Organic Letters 2002 4 (19), 3309-3311 {{doi, 10.1021/ol0265822 Asymmetric Hetero-Diels–Alder Reaction of Danishefsky's Dienes with α-Carbonyl Esters Catalyzed by an Indium(III)–PyBox Complex Bei Zhao and Teck-Peng Loh Organic Letters 2013 15 (12), 2914-2917 {{doi, 10.1021/ol400841s ''A Highly Enantioselective Hetero-Diels−Alder Reaction of Aldehydes with Danishefsky's Diene Catalyzed by Chiral Titanium(IV) 5,5',6,6',7,7',8,8'-Octahydro-1,1'-bi-2-naphthol'' Complexes Bin Wang, Xiaoming Feng, Yaozong Huang, Hui Liu, Xin Cui and Yaozhong Jiang The Journal of Organic Chemistry 2002 67 (7), 2175-2182 {{doi, 10.1021/jo016240u ''Alkaline salt-catalyzed aza Diels–Alder reactions of Danishefsky's diene with imines in water under neutral conditions'' Catherine Loncaric, Kei Manabea and Shū Kobayashi Chem. Commun., 2003, 574-575 {{doi, 10.1039/B300880K ''Exo selective Diels–Alder reaction of nitroolefins with Danishefsky's diene'' Manabu Node, Kiyoharu Nishide, Hitoshi Imazato, Ryuichi Kurosaki, Takehisa Inoue and Takao Ikariya Chem. Commun., 1996, 2559-2560 {{doi, 10.1039/CC9960002559 ''Zheng, J., Lin, L., Fu, K., Zhang, Y., Liu, X. and Feng, X. (2014), Asymmetric Hetero-Diels–Alder Reaction of Danishefsky's Diene with α-Ketoesters and Isatins Catalyzed by a Chiral N,N′-Dioxide/Magnesium(II) Complex.'' Chem. Eur. J., 20: 14493–14498. {{doi, 10.1002/chem.201404144 ''Development of an unusually highly enantioselective hetero-Diels-Alder reaction of benzaldehyde with activated dienes catalyzed by hypercoordinating chiral aluminum complexes'' Simonsen KB1, Svenstrup N, Roberson M, Jorgensen KA. Chemistry. 2000 Jan;6(1):123-8. {{PMID, 10747395 ''Catalytic enantioselective aza-Diels-alder reactions of imines--an approach to optically active nonproteinogenic alpha-amino acids'' Yao S, Saaby S, Hazell RG, Jorgensen KA. Chemistry. 2000 Jul 3;6(13):2435-48. {{PMID, 10939745 ''Total syntheses of the Securinega alkaloids (+)-14,15-dihydronorsecurinine, (−)-norsecurinine, and phyllanthine.'' Han G, LaPorte MG, Folmer JJ, Werner KM, Weinreb SM. J Org Chem. 2000 Oct 6;65(20):6293-306. {{PMID, 11052071 ''Racemic and asymmetric Diels-Alder reactions of 1-(2-oxazolidinon-3-yl)-3-siloxy-1,3-butadienes.'' Janey JM, Iwama T, Kozmin SA, Rawal VH.J Org Chem. 2000 Dec 29;65(26):9059-68.{{PMID, 11149852 ''Total asymmetric synthesis of the putative structure of the cytotoxic diterpenoid (−)-sclerophytin a and of the authentic natural sclerophytins A and B.'' Bernardelli P, Moradei OM, Friedrich D, Yang J, Gallou F, Dyck BP, Doskotch RW, Lange T, Paquette LA. J Am Chem Soc. 2001 Sep 19;123(37):9021-32. {{doi, 10.1021/ja011285y ''Difluorinated Danishefsky's diene: a versatile C(4) building block for the fluorinated six-membered rings.'' Amii H, Kobayashi T, Terasawa H, Uneyama K. Org Lett. 2001 Oct 4;3(20):3103-5. {{doi, 10.1021/ol0163631 ''A straightforward stereoselective synthesis of D- and L-5-hydroxy-4-hydroxymethyl-2-cyclohexenylguanine''. Wang J, Morral J, Hendrix C, Herdewijn P.J Org Chem. 2001 Dec 14;66(25):8478-82. {{doi, 10.1021/jo015924z ''Chiral hetero Diels-Alder products by enantioselective and diastereoselective zirconium catalysis. Scope, limitation, mechanism, and application to the concise synthesis of (+)-Prelactone C and (+)-9-deoxygoniopypyrone''. Yamashita Y, Saito S, Ishitani H, Kobayashi S.J Am Chem Soc. 2003 Apr 2;125(13):3793-8. {{doi, 10.1021/ja028186k ''Enantioselective catalysis of hetero Diels-Alder reaction and diethylzinc addition using a single catalyst''. Du H, Ding K.Org Lett. 2003 Apr 3;5(7):1091-3. {{doi, 10.1021/ol034143c Conjugated dienes Trimethylsilyl compounds Reagents for organic chemistry