1-Heptene hydroxylation

The Diels-Alder reaction was utilized to construct bicyclo [2.2 1]heptane or bicyclo[2 2 l]heptene structures The reaction of isopropylidenecyclopentadiene with maleic anhydride produced the endo and exo configurational isomers of 8-isopropylidenebicyclo[2.2.1] hept-2-ene-5,6-dicarboxylic anhydride Similar reactions were applied to unsubstituted and l-(methoxycarbonyl)cyclopentadienes to give the corresponding anhydrides The anhydrides were reduced to alcohols, which were then allowed to react with thionyl chloride or tosyl chloride to give cyclic sulfites or tosylates Reaction of the tosylates with lithium chloride gave chlorinated compounds Hydration of the double bonds of the chlorinated compounds was accomplished by hydroboration-oxidation Diol 31 thus obtained was converted to 5,6-bis(chloromethyl)-7-isopropylidene-bicyclo[2 2 1] heptan-2-one [33] by chromium trioxide oxidation of the secondary hydroxyl group followed by dehydration at the C-7 substituent. 

Water is removed with especial ease from alcohols whose hydroxyl group is in a /9-position to an oxo, alkoxycarbonyl, nitrile, or nitro group. For example, on aldolization of acetaldehyde the acid present in the reaction medium suffices for dehydration of the product to the unsaturated carbonyl compound, i.e., to crotonaldehyde. One hour s boiling with dilute sulfuric acid suffices for preparation of 3-hepten-2-one from 4-hydroxy-2-heptanone 39... 

The key transformation, a Hiyama reaction of l-bromo-2-( )-heptene with 970, produces the Felkin—Anh product 971 with >99 1 diastereoselectivity. The key to accessibility to the four stereoisomers of blastmycinolactol is the differentiated 2- and 3-hydroxyl groups in 971. 

Diels-Alder Reactions. Bp3-OEt2 is used to catalyze and reverse the regiospecificity of some Diels-Alder reactions, e.g. with pen-hydroxylated naphthoquinones, sulfur-containing conpounds, the reaction of 1-substituted trans-1,3-dienes with 2,6-dimethylbenzoquinones, and the reaction of 6-inethoxy-l-vinyl-3,4-dihydronaphthalene with p-quinones. BFs-OEta has a drastic effect on the regioselectivity of the Diels-Alder reaction of quinoline- and isoquinoline-5,8-dione with piperylene, which produces substituted azaanthraquinones. This Lewis acid is the most effective catalyst for the Diels-Alder reaction of furan with methyl acrylate, giving high endo selectivity in the 7-oxabicyclo[2.2.1]heptene product (eq 35). ... 

In addition, an imspecific peroxygenase secreted by the fungus Agrocybe aegerita was used in the oxidation of 20 different alkenes. Besides epoxidation, hydroxylation also occmred in a lot of cases with peroxygenase as catalyst. The stereoselectivitiesto-ward n-hexene, n-heptene, and n-octene were reported to be 67%, 72%, and 66% ee, respectively, for the (S)-enantiomers [93]. 

O rji, L.N., and D.A. Stone (1992), Relative rate constant measurements for the gas-phase reactions of hydroxyl radicals with 4-methyl-2-pentanone, trans-4-octene, and trans-2-heptene, Int. J. Chem. Kinet., 24, 703-710. 

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