51068-02-1Relevant articles and documents
DOMINANT cis-DIACETOXYLATION OF ALKENES WITH TELLURIUM(IV) OXIDE AND LITHIUM BROMIDE IN ACETIC ACID
Uemura, Sakae,Ohe, Kouichi,Fukuzawa, Shin-Ichi,Patil, Suresh R.,Sugita, Nobuyuki
, p. 67 - 78 (1986)
Oxidation of alkenes with tellurium(IV) oxide and lithium bromide in acetic acid affords the corresponding α,β-diacetoxyalkanes in good yields after acetylation of the primary products with acetic anhydride/pyridine.From cyclic alkenes such as cyclopentene, cyclohexene, cycloheptene, and 1,4-cyclohexadiene, the cis-diacetate is obtained as almost the sole product.In the cases of linear cis alkenes such as cis-2-octene and cis-4-octene cis-stereochemistry is also preferred (cis/trans = 87-89/13-11), while the proportion of the cis-product is decreased in the cases of the corresponding trans-alkenes (cis/trans = 56-58/44-42).Transformation of a C-Te bond to a C-OAc bond under these reaction conditions is shown unambiguously by using β-chloroalkyltellurium(IV) trichlorides (TeCl4 adducts of alkenes) and β-oxyalkyl phenyl tellurides (oxytellurenylation products of alkenes), cis-diacetates being solely formed from the trans-tellurium compounds in a cyclohexyl system.One of the possible reaction patways for the oxidation is proposed which involves the acetoxy-, hydroxy-, and/or halogeno-tellurinylation of a double bond followed by an SN2 type acetolysis of the produced C-Te bond.
Preparation of Optically Active γ-Hydroxyethyl α,β-Unsaturated γ-Lactone Using an Enzymatic Procedure
Suemune, Hiroshi,Hizuka, Michiyo,Kamashita, Tomoko,Sakai, Kiyoshi
, p. 1379 - 1381 (2007/10/02)
γ-Hydroxyethyl α,β-unsaturated γ-lactone (2) is a promising intermediate for the synthesis of eldanolide and cis,cis-1,2,3-trisubstituted cyclopentane, which could be converted to 11-deoxyprostaglandins.In order to prepare optically active 2, enzymatic hy
