652993-59-4Relevant academic research and scientific papers
Enantiomerically pure cyclopropylamines from cyclopropylboronic esters
Pietruszka, Joerg,Solduga, Gemma
supporting information; experimental part, p. 5998 - 6008 (2010/03/01)
Cyclopropylamines are versatile intermediates and products both in organic synthesis in general and for active substances in particular. Although the synthesis of the corresponding enantiomerically pure cyclopropylboronic esters had been established previously, the C-B to C-N transformation was elusive. A detailed, study directed towards the synthesis of several enantiomerically pure cyclopropylamines is disclosed; tranylcypromine [(1S, 2R)-36] and the known belactosin A intermediate 43 were both obtained by use of trifluoroborates as key intermediates.
Diastereo- and enantiomerically pure allylboronates: Their synthesis and scope
Pietruszka, Joerg,Schoene, Niklas,Frey, Wolfgang,Grundl, Li
experimental part, p. 5178 - 5197 (2009/07/18)
Allylboronates are highly attractive reagents for allyl additions. Enantiomerically pure, stable reagents with a stereogenic centre in a-position to boron are especially versatile, albeit often difficult to synthesize. Starting from boron-containing allyl alcohols 6 and 7, which are discussed in detail herein, a set of reagents were obtained via [3,3]-sigmatropic rearrangements and consecutive transformations in the side chain. The configurations could be established first by chemical correlation, but also by X-ray crystallography (16, 18, 34, and 39). Allyl additions were performed resulting in the formation of predominantly (Z)-configured homoallylic alcohols (31, 43-45) with high enantiomeric excess. Detailed investigations on the matched-mismatched interaction between the reagents 15/16 (and ent-15/ent-16, respectively) and isopropylidene glyceraldehyde 42 d are presented.
[3,3] Sigmatropic Rearrangement of Boron-Containing Allyl Alcohols: Synthesis of Allyl Addition Reagents
Pietruszka, Joerg,Schoene, Niklas
, p. 5638 - 5641 (2007/10/03)
Enantiomerically pure reagents for allyl additions were prepared by [3,3] sigmatropic rearrangements (see scheme) followed by a separation of the diastereoisomers. The highly stable allylboronic esters with a stereogenic center α to a boron atom were used to synthesize Z-configured homoallylic alcohols with an enantiomeric excess > 94%.
