In organic chemistry, atoms other than carbon and hydrogen are generally referred to as heteroatoms. The most common heteroatoms are nitrogen, oxygen and sulfur. Now I present to you an article called Synthesis of Enantiopure Piperazines via Asymmetric Lithiation-Trapping of N-Boc Piperazines: Unexpected Role of the Electrophile and Distal N-Substituent, published in 2016-01-20, which mentions a compound: 138775-03-8, mainly applied to synthesis enantiopure piperazine; asym lithiation piperazine, SDS of cas: 138775-03-8.
A new method for the synthesis of enantiopure α-substituted piperazines via direct functionalization of the intact piperazine ring is described. The approach utilizes the asym. lithiation-substitution of an α-methylbenzyl-functionalized N-Boc piperazine using s-BuLi/(-)-sparteine or (+)-sparteine surrogate and provides access to a range of piperazines (as single stereoisomers). Optimization of the new methodol. required a detailed mechanistic study. Surprisingly, it was found that the main culprits affecting the yield and enantioselectivity were the electrophile (the last reagent to be added to the reaction flask) and the distal N-substituent. The mechanistic studies included optimization of lithiation times using in situ IR spectroscopy, identification of a ring-fragmentation of the lithiated piperazines (that could be minimized with sterically hindered N-alkyl groups), and use of a novel “”diamine switch”” strategy to improve enantioselectivity with certain electrophiles. The methodol. was showcased with the preparation of an intermediate for Indinavir synthesis and the stereoselective synthesis of 2,5-trans- and 2,6-trans-piperazines.
If you want to learn more about this compound((S)-4-((Benzyloxy)carbonyl)-1-(tert-butoxycarbonyl)piperazine-2-carboxylic acid)SDS of cas: 138775-03-8, you may wish to communicate with the author of the article,or consult the relevant literature related to this compound(138775-03-8).
Reference:
Iodide – Wikipedia,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com