Cis-Jasmone synthesis

Jacobson-Hugershofi synthesis benzothiazoles, 5, 135 Japp-KJingemann reaction JV-arylhydrazones from, 4, 337 1,2,4-triazole synthesis by, 5, 768 Jasmine lactone synthesis, 3, 847 Jasminine occurrence, 2, 626 y-Jasmolactone synthesis, 4, 674 cis-Jasmone synthesis, 1, 422, 427 Jatropham synthesis, 1, 426 Josephson junctions, 1, 359 Juliprospine... 

An unsymmetrical example is the allylic halide 19 needed for the synthesis of cis jasmone. Obvious disconnections take us back to 21 and a simple three-component synthesis. 

Enol ethers react with diazo ketones in the presence of Cu-catalysts to give cyclopropanes such as 24. Ring cleavage with acid and subsequent intramolecular aldol condensation constitutes a flexible route to cyclopentenones (Eq. 7) 12-13). This procedure has also been applied to a synthesis of cis-jasmone employing isopropenyl acetate as a donor olefin 14). 

This reaction is important in a synthesis of the perfumery compound ds-jasmone. The alkyne is the precursor to cis-jasmone s alkene side chain. 

This new synthesis of 1,4-diketones was used in a synthesis of cis-jasmone (6). 

For d1 reagents which will add Michael fashion to any unsaturated carbonyl compound, amino-nitriles are best. They were invented by Stork13 for this very purpose and used in his cis jasmone 65 synthesis. This TM has perhaps been more synthesised than any other, though its simple structure and obvious enone disconnection to 66 make it a rather uninspiring choice these days. The 1,4-diketone 66 does indeed cyclise to 65 presumably under thermodynamic control, and the double disconnection 66 [cf. the disconnection of pyrenophorin 23] requires a d1 reagent that will react with enones 67 in the Michael sense and with alkyl halides 69. 

Syntheses of jasmone and closely related compounds continue unabated. Previous syntheses in this area have been collated.McMurray and Abe have effected selective ozonolysis of an enyne derivative in their synthesis of cis-jasmone (486) which is outlined in Scheme 26. 

A synthesis of dihydrojasmone (493) and cis-jasmone (486) has been reported which centres on the formation of 1,4-diketones.Compound (492) was derived from acyloin condensation of methyl levulinate ethylene acetal in the presence of tri-methylchlorosilane the subsequent sequence is outlined in Scheme 27. By means of... 

Stetter H, Kuhlmann H (1975) Addition of Aldehydes to Activated Double Bonds. 7. New Simple Synthesis of cis-Jasmon and DUiydrojasmon. Synthesis 379... 

Several synthesis of the Prelog-Djerassi lactone elevate the compound almost to the position of cis-jasmone in terms of its popularity as a synthetic target. Full details of the Danishefsky route to ( )-quadrone have appeared as well as a report of a concurrent synthesis. A new method for the preparation of 5-lactones involving the reaction of a y,5-unsaturated aldehyde with NaOH followed by oxidation has been applied to the synthesis of ( )-pentaleno-lactone. The first total synthesis of (+)-compactin has been reported. ... 

Electrophilic Cleavage and Oxidation of Cyclobutane Derivatives. Periodic acid in aqueous THF cleaves a 1,2-dioxygenated cyclobutane to a 1,4-diketone in a new synthesis of cis-jasmone. Mono- and bis-l,2-dioxetans (232) and (233) may be made by photosensitized oxygenation of the dibenzylidenecyclo-butane (231). Subsequent reductive reactions can be used to open the cyclobutane ring of (233). 

Owing to its long-standing limitations, the Stetter reaction has been utQized in a limited number of syntheses (Figure 18.4). P-Unsubstituted acceptors have been used en route to cis-jasmone and dihydrojasmone [57], roseophilin (81) [58], ( )-trans-sabinene hydrate [59], monomorine I [60], and haloperidol [61], while a doubly activated Michael acceptor was used to access an intermediate in the synthesis of atorvastatin [62]. Less reactive P-substituted acceptors could be used intramolecularly in the syntheses of ( )-hirsutic acid C (82) [63], ( )-platensimycin (83) [64], and polycyclic ether arrays [65], as well as in the enantioselective formation of a spirocyclic intermediate toward FD-838 (84) [66]. 

The jasmonates are another class of disubstituted cyclopentanoid natural products very reminiscent of the prostaglandins. To efficiently assemble their main skeleton, Yamamoto and co-workers developed a clever three-component reaction methodology that was demonstrated by the total synthesis of both trans- and cis-methyl jasmonates 36 and 37 (Scheme 12.7) [25],... 

---