Modified Julia Olefination on Anhydrides: Extension and Limitations. Application to the Synthesis of Maculalactone B

Abstract

The preparation of exo-enol esters from cyclic anhydrides is reported using a modified Julia olefination. The reaction is highly stereoselective. The Smiles rearrangement can be performed in a one-pot process, giving a straightforward access to exo-enol lactones. Furthermore, the reaction was extended to semistabilized sulfones, and this methodology was applied to the synthesis of maculalactone B.

Electrochemically Induced Synthesis of Sulfonylated N-Unsubstituted Enamines from Vinyl Azides and Sulfonyl Hydrazides

“…The sulfonyl group is present in many agrochemical , and medicinal − agents. SO 2 -containing molecules are often applied for the construction of double bonds − and heterocycles, − as well as in arylation reactions. − Thus, the structures which have both N -unsubstituted enamine and sulfonyl fragments are quite useful in organic and medicinal chemistry.…”

Preparation of 3‐Alkylidenephthalides: Recent Advances

“…Recently, Gueyrard and co‐workers described an effective modified Julia olefination from the preparation of benzalphthalides from phthalic anhydrides and tetrazolyl sulfone (Scheme 3). [8] In optimized conditions, the E‐ configured heterocycles ( E / Z : from 80/20 to 95/5) were generally obtained in good yields whatever the nature of the tetrazolyl sulfone. For examples, alkyls and terminal alkenes groups as well as protected alcohols are well tolerated.…”

Julia‐Kocienski Olefination: A Tutorial Review

“…[43] Generally, the JK reagents with simple alkyl substituents on the sulfur atom are prepared via alkylation with corresponding halides 81. [44] Alternatively, the alcohol 80 can be first mesylated and then treaded with 79 in a one-pot setting to give the desired sulfides 78 in good yields. [45] In the case of more complex and sensitive substrates, a Mitsunobu reaction of the corresponding alcohol 80 and tetrazole thiol 79 is employed which is considered to be milder than the alkylation (Scheme 10, B).…”