158039-55-5Relevant academic research and scientific papers
Aminolysis of vinyl epoxides as an efficient entry to N-H vinylaziridines
Lindstroem, Ulf M.,Somfai, Peter
, p. 109 - 117 (2007/10/03)
Vinyl epoxides 8a-f 11 and 12 have been prepared from the corresponding epoxy alcohols while 8g was formed by a regioselective epoxidation of the parent diene. Aminolysis of these materials resulted in a regio- and stereoselective nucleophilic opening at C3 in good yields except for the sterically hindered substrates. The trans-oxiranes gave the anti-amino alcohols while the cis derivative 12 gave the syn isomer 17. Cyclization of the anti-amino alcohols was best effected using the Mitsunobu protocol giving the corresponding N-H vinylaziridines in 50-54% yields, while the syn-amino alcohol 17 was transformed into the cis-vinylaziridine 31 with chlorosulfonic acid followed by base treatment in 20% yield. The outcome of these cyclizations seems to indicate that they are controlled by subtle steric effects in the substrate. The N-H vinylaziridine 24 was alkylated with tert-butyl bromoacetate and the product subjected to an aza[2,3]-Wittig rearrangement to give tetrahydropyridine 30 while acetylation of 24 followed by base treatment resulted in an aza-[3,3]-Claisen rearrangement yielding the seven-membered lactam 32.
Convenient asymmetric syntheses of anti-β-amino alochols
Barrett, Anthony G. M.,Seefeld, Mark A.,White, Andrew J. P.,Williams, David J.
, p. 2677 - 2685 (2007/10/03)
Condensation of allylborane reagents 9 and 12 with aldehydes gave anti-3-[(diphenylmethylene)-amino]-1-alken-4-ols 10 and 13 with high relative and absolute stereocontrol. Subsequent deprotection gave the corresponding free anti-3-amino-1-alken-4-ols 11 and 14. Alternatively, reaction of imines 13a, 13f, and 13g with trifluoromethanesulfonic anhydride and acidic methanol gave, via rearrangement, double inversion, and hydrolysis, the isomeric anti-4-amino-1-alken-3-ols 22, 38a, and 38b in good yield. The stereochemistry of the rearrangement products has been established by a single crystal X-ray study of compound 37 and by chemical correlation.
