A concise route to d-erythro-sphingosine from N-Boc-l-serine derivatives via sulfoxide or sulfone intermediates
摘要:
Sulfoxide and sulfone intermediates 7 and 15, respectively, were employed to synthesize synthons 3 and 4, which are readily converted to the naturally occurring (2S,3R,4(E))-sphingosine 1 and (2S,3R)-sphinganine 2. (C) 2002 Elsevier Science Ltd. All rights reserved.
A concise route to d-erythro-sphingosine from N-Boc-l-serine derivatives via sulfoxide or sulfone intermediates
摘要:
Sulfoxide and sulfone intermediates 7 and 15, respectively, were employed to synthesize synthons 3 and 4, which are readily converted to the naturally occurring (2S,3R,4(E))-sphingosine 1 and (2S,3R)-sphinganine 2. (C) 2002 Elsevier Science Ltd. All rights reserved.
N-methylation of sulfoximines using methylboronic acid is reported. The reactions provide excellent yields in a short span of time under mild conditions. The optimized conditions were also found to be suitable for the N-alkylation of sulfoximine with different alkylboronic acids. In addition, N-methylation and cyclopropylation of the bioactive L-methionine sulfoximine derivative was demonstrated under standard
Asymmetric Palladium-Assisted Alkylation of Alkenes
作者:Arlette Solladié-Cavallo、Jean-Luc Haesslein
DOI:10.1002/hlca.19830660615
日期:1983.9.21
Palladium-promoted alkylation of alkenes using chiral sulfoxide-containing carbanions and chiral lithiated oxazolines results in asymmetric induction (AI) ranging from 3–5% (1,5 induction), 20–40% (1,3 induction) to 44–52% (1,4 induction). No general trend allowing predictions of results was found. With 1-hexene, attack at C(1) is almost exclusive but propene gives a mixture of attack at C(1) and C(2)
Selective manganese-mediated transformations using the combination:
作者:István E Markó、Paul R. Richardson、Mark Bailey、Anita R. Maguire、Niall Coughlan
DOI:10.1016/s0040-4039(97)00309-2
日期:1997.3
A novel manganese reagent, generated from KMnO4 and Me3SiCl, in the presence of a quaternaryammonium salt, is shown to smoothly dichlorinate alkenes, open epoxides and chemoselectively oxidise sulfides to sulfoxides.