137764-92-2Relevant academic research and scientific papers
A highly stereoselective preparation of syn-1,2-diols from secondary α-allenic alcohols via iodocyclization. Synthesis of (±)-threo-L-factor and (±)-disparlure
Friesen,Giroux
, p. 1857 - 1865 (2007/10/02)
The iodocyclization of the N-tosyl carbamates 5 of secondary α-allenic alcohols 4 is described. The reaction sequence involves the addition of iodine to the terminal olefin of the allene moiety of 5 resulting in the formation of an isomeric mixture of Z and E diiodides 6 and 7. This initial process is followed, in the same pot, by reaction of the diiodides with silver carbonate. Hydrolysis of the resulting trans imino carbonates 8 provides syn-1,2-diols 10 in highly diastereoselective (>50:1) and regioselective (>20:1) fashion. Oxazolidinones 9 are minor products that arise from the participation of the carbamate nitrogen atom in the cyclization reaction. The regioselectivity of the cyclization reaction from 6/7 to 8 is highly dependent upon the reaction solvent with the optimum results being obtained in ether/MeCN mixtures (10:1 to 50:1) or CH2Cl2. The synthetic utility of the vinyl iodo diols 10 is demonstrated by the synthesis of (±)-threo-5-hydroxy-4-decanolide (17) ((±)-threo-L-factor) and (±)-cis-7,8-epoxy-2-methyloctadecane (24) ((±)-disparlure). The key step in each synthesis involves the conversion of the vinyl iodide moiety of 10 into the alkynes 15 or 18 (from 10j and 10k, respectively) via a high-yielding dehydrohalogenation reaction.
Enantioselective Route to α-Hydroxy Aldehyde and Acid Derivatives
Corey, E. J.,Jones, Graham B.
, p. 5713 - 5716 (2007/10/02)
Methodology is described for the enantioselective synthesis of chiral O-protected α-hydroxy aldehydes, acids and esters from achiral aldehydes having one less carbon.
Iodocyclization of the (Tolylsulfonyl)- and (Trichloroacetyl)carbamates of Secondary α-Allenic Alcohols. Highly Diastereoselective Synthesis of syn-1,2-Amino Alcohols and trans-5-Alkyl-1-oxo-2-oxazolidine-4-carboxylic Acids
Friesen, Richard W.,Kolaczewska, Aleksandra E.
, p. 4888 - 4895 (2007/10/02)
The iodocyclization of tosyl- and (trichloroacetyl)carbamates 9 and 10, respectively, of secondary α-allenic alcohols is described.The cyclofunctionalization reactions are highly diastereoselective, providing trans-5-alkyl-4-(1-iodoethylene)-2-oxazolidino
A HIGHLY STEREOSELECTIVE CONVERSION OF α-ALLENIC ALCOHOLS TO 1,2-SYN AMINO ALCOHOL DERIVATIVES VIA IODOCARBAMATION
Friesen, Richard W.
, p. 4249 - 4252 (2007/10/02)
The iodocarbamation of α-allenic alcohol O-carbamates is described.Reactions carried out in anhydrous Et2O are highly diastereoselective, providing the cyclic carbamates trans-8 and cis-9 in ratios ranging from 21:1 to >99:1.Hydrolysis and acetylation pr
