Cycloaddition “4 + 2” reactions of levoglucosenone

Ward, David D.; Shafizadeh, Fred

doi:10.1016/s0008-6215(00)85573-1

Cited by 54 publications

(13 citation statements)

References 24 publications

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“…W ith this enone, exo addition of dienes is favored, 1,3butadiene giving crystalline 249 in 95 % yield following reaction at 160 °C. 131 For cyclic dienes the situation is more complex, the alkene group developed during the reaction being able to adopt exo or endo orientations with respect to the pyranoid ring, and cyclopentadiene giving the isomeric exo adducts 253 and 254 in 65 and 16% yield, respectively, following heating together or in boiling chlorobenzene.131-133 1,3-Cyclohexadiene, 1,3diphenylisobenzofuran,131 and l,2,3,4-tetrachloro-5,5-dimethoxycyclopentadiene133 also give products of cycloaddition in high yield. Further functionalized derivatives became available by use of modified dienes, Because of its relatively low availability, fewer studies have been carried out on "isolevoglucosenone" (260), but when treated with cyclopentadiene, with zinc chloride present as catalyst, it gave both products 261 and 262 of "down" addition in 82 % yield and in the proportions 4:1 (Scheme 49).…”

Section: Scheme 43mentioning

confidence: 99%

The conversion of carbohydrate derivatives into functionalized cyclohexanes and cyclopentanes

Ferrier¹,

Middleton²

1993

Chem. Rev.

422

146

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Section: Scheme 43mentioning

confidence: 99%

The conversion of carbohydrate derivatives into functionalized cyclohexanes and cyclopentanes

Ferrier¹,

Middleton²

1993

Chem. Rev.

422

146

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“…The development of new transformations that utilize LGO is crucial to make use of this biorenewable resource. Reactions previously reported for LGO include the reaction of the alkene with electrophiles,3 cycloaddition reactions,4 redox chemistry,1b and conjugate addition chemistry 5. First investigated by Shafidazeh et al,6 the Baeyer–Villiger reaction of LGO was used extensively by Ebata et al to generate butyrolactones that include naturally occurring eldanolide and whiskey lactone 7.…”

Section: Introductionmentioning

confidence: 99%

Palladium‐Catalyzed Suzuki–Miyaura, Heck and Hydroarylation Reactions on (–)‐Levoglucosenone and Application to the Synthesis of Chiral γ‐Butyrolactones

et al. 2015

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The chiral pool material (–)‐levoglucosenone (6,8‐dioxabicyclo[3.2.1]oct‐2‐en‐4‐one, LGO) has been substituted by using a series of Pd‐mediated cross‐coupling reactions. Iodination of LGO followed by Suzuki–Miyaura cross‐coupling reaction with boronic acids by employing the Buchwald ligand SPhos with Pd(OAc)2 afforded 3‐aryl derivatives in excellent yields. Selective Heck arylation reaction at the 2‐position was achieved with aryl iodides with K3PO4 as base and SPhos ligand with Pd(OAc)2 (1–5 mol‐%). A selective hydroarylation reaction (formal conjugate addition) was developed by using the same aryl iodides, benzyldiethylamine, Pd(OAc)2, and P(o‐tol)3. The products were converted, either directly or after alkene reduction, through a Baeyer–Villiger oxidation into chiral 3‐ and 4‐substituted 5‐(hydroxymethyl)dihydrofuran‐2(3H)‐ones.

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“…We have also described recently a convenient synthesis of 2-alkoxy-2 H -pyran-3(6 H )-ones starting from d -xylose, and proved their usefulness as dienophiles in Diels−Alder reactions with butadienes. In fact, [4+2] cycloadditions of a number of structurally related pyranones, such as 2-alkoxy-2 H -pyran-5(6 H )-ones, 2-alkoxy-4- O -benzoyl-6-benzoyloxymethyl-2 H -pyran-3(6 H )-ones (enolones), levoglucosenone, and isolevoglucosenone, have been conducted in order to obtain optically pure carbocyclic derivatives.…”

Section: Introductionmentioning

confidence: 99%

Stereocontrolled Diels−Alder Cycloadditions of Sugar-Derived Dihydropyranones with Dienes

Capaccio

Varela

2002

J. Org. Chem.

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2-Acetoxy-3,4-di-O-acetyl-D-arabinal (6), similar to its D-xylo analogue 4, reacted with benzyl alcohol by the tin(IV) chloride-promoted glycosylation to produce optically active (S)-2-benzyloxy-2H-pyran-3(6H)-one (8a). The L-arabinal derivative (5) gave 9a, the dihydropyranone enantiomer of 8a. These results indicated that the configuration of the C-4 stereocenter in the starting glycal defines the configuration of the new chiral center in the resulting dihydropyranone. The influence of other catalysts (BF(3) or iodine) employed for the glycosylation on the optical purity of the dihydropyranone was studied. Enantiomerically pure dihydropyranones 8b and 9c were obtained using chiral alcohols ((R)- and (S)-2-octanol, respectively) as glycosylating agents. Compounds 8a,b and 9a,c proved to be reactive dienophiles in thermal and Lewis acid-promoted Diels-Alder reactions. The addition of 2,3-dimethylbutadiene, cyclopentadiene, and 1,3-cyclohexadiene to the beta-pyranones 8a,b led to the corresponding adducts 10a,b, 12a,b, and 16a,b as major products. Enantiomeric cycloadducts were synthesized from the alpha-pyranones 9a,c. The main products were formed by highly facial-diastereoselective addition of dienes to the pyranone ring, guided by the sterical hindrance of the alkoxy substituent of the C-2 stereocenter. As cycloadditions with cycloalkadienes were also highly endo diastereoselective, these reactions gave access to pure tetrahydrobenzopyranones that carry a multitude of stereogenic centers installed in a predictable way.

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Cycloaddition “4 + 2” reactions of levoglucosenone

Cited by 54 publications

References 24 publications

The conversion of carbohydrate derivatives into functionalized cyclohexanes and cyclopentanes

The conversion of carbohydrate derivatives into functionalized cyclohexanes and cyclopentanes

Palladium‐Catalyzed Suzuki–Miyaura, Heck and Hydroarylation Reactions on (–)‐Levoglucosenone and Application to the Synthesis of Chiral γ‐Butyrolactones

Stereocontrolled Diels−Alder Cycloadditions of Sugar-Derived Dihydropyranones with Dienes

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