62090-89-5Relevant academic research and scientific papers
STEREOSELECTIVE SYNTHESIS OF 2-(2'-CYCLOALKENYL)GLYCINATES VIA ESTER-ENOLATE CLAISEN REARRANGEMENT
Bartlett, Paul A.,Barstow, James F.
, p. 623 - 626 (1982)
Ester-enolate Claisen rearrangement of 2-cycloalkenyl N-t-Boc-glycinates leads to the biologically active RS,SR-diastereomers selectively.
Stereoselective synthesis of 2-(2'-cycloalkenyl) glycinates via [3,3] sigmatropic rearrangement of chelated ester-enolates
Kazmaier
, p. 12895 - 12902 (2007/10/02)
Ester-enolate Claisen rearrangement of chelated N-protected cycloalkenyl glycinates 1 results in the formation of cyclic γ,δ-unsaturated amino acids in good yields and in a highly diastereoselective fashion.
Ester-Enolate Claisen Rearrangement of α-Amino Acid Derivatives
Bartlett, Paul A.,Barstow, James F.
, p. 3933 - 3941 (2007/10/02)
With the standard procedure for the Ireland-Claisen rearrangement, using 2 equiv of base, allylic esters of N-acyl α-amino acids are converted to the rearranged γ,δ-unsaturated α-amino acids in moderate to good yield and diastereoselectivity.Moderate variation, but not reversal, of stereoselectivity is seen on using different solvents or conditions.Variation in the substituents on the amino group, α-position, and allylic alcohol moiety was also studied.For each case in which the stereochemistry of the rearranged product was proven, it was consistent with predominant formation of the E enolate (enolate oxygen and anionic acylamido substituent cis).The rearrangement was also apllied successfully to the synthesis of highly hindered amino acids and to cyclo-alkenyl-substituted analogues.In a number of instances, comparison was made with an alternative rearrangement procedure involving an oxazole intermediate.
