Boranes in Synthesis. 1. Asymmetric synthesis of β-amino alcohols. A facile conversion of enamines to the corresponding β-amino alcohols in high enantiomeric purity
作者:Gary B. Fisher、Christian T. Goralski、Lawrence W. Nicholson、Bakthan Singaram
DOI:10.1016/s0040-4039(00)61541-1
日期:1993.11
The asymmetric hydroboration of aldehyde enamines with dIpc2BH at 0 °C, followed by oxidation with NaOH(s)/H2O2, yields the corresponding β-amino alcohols in good yields and high enantiomeric excess.
醛烯胺与d Ipc 2 BH在0°C下不对称氢硼化,然后用NaOH / H 2 O 2氧化,得到相应的β-氨基醇,收率高,对映体过量高。
Beta-Substituted Tetrahdropyrana (On) S And Method For The Synthesis And The Use Thereof
申请人:Mane Jean
公开号:US20080032914A1
公开(公告)日:2008-02-07
The invention relates, in particular to a tetrahydropyran(on) compound which is substituted in position beta with respect to a cycle oxygen of formula (I), wherein a substituent R is a linear alkyl radical in C2:C10 including, (CH
3
)
2
CH— or C
6
H
5
—(CH
2
)
m
—, with m=0 or 1, or formula (II), wherein A is —CH
2
— or —CO—, in the form of an odorant and to a method for the synthesis thereof by reducing oxo-ester. The use of the inventive compound in composition such as perfumery compositions in the ordinary sense of the term i.e. topic, in particular cosmetic compositions and care products.
作者:Sucrow, Wolfgang、Minas, Hermann、Stegemeyer, Horst、Geschwinder, Peter、Murawski, Hans-Ruediger、Krueger, Carl
DOI:——
日期:——
Boranes in Synthesis. 5. The Hydroboration of Enamines with Mono- and Dialkylboranes. Asymmetric Synthesis of .beta.-Amino Alcohols of Moderate Enantiomeric Purity from Aldehyde Enamines
作者:Gary B. Fisher、Christian T. Goralski、Lawrence W. Nicholson、Dennis L. Hasha、Donald Zakett、Bakthan Singaram
DOI:10.1021/jo00112a026
日期:1995.4
The hydroboration of both acyclic and cyclic aldehyde and ketone enamines with such representative mono- and dialkylboranes as thexylborane and dicyclohexylborane, followed by an oxidative workup, yields the corresponding beta-amino alcohols in good to excellent isolated yields. The hydroboration of ketone and aldehyde enamines with the asymmetric hydroboration reagents monoisopinocampheylborane ((d)IpcBH(2)) and diisopinocampheylborane ((d)Ipc(2)BH) was also investigated, (d)Ipc(2)BH is highly effective for the asymmetric hydroboration of acyclic aldehyde enamines, such as 1-(4-morpholino)-3-phenyl-1-propene and 1-(1-pyrrolidino)-1-octene. Oxidation of the intermediate trialkylborane furnishes the corresponding beta-amino alcohols in 50-86% ee. The stereogenic center of the carbinol carbon is consistently enriched in the R-enantiomer when (d)Ipc(2)BH prepared from (+)-alpha-pinene is used as the hydroboration reagent. The enantiomeric excesses of the beta-amino alcohols synthesized in this study were determined by HPLC using a chiral stationary phase. The absolute configurations of some of the beta-amino alcohols synthesized in this study were determined by chiral HPLC comparison with authentic beta-amino alcohols prepared from chiral epoxides of known absolute configuration.
SUCROW, W.;MINAS, H.;STEGEMEYER, H.;GESCHWINDER, P.;MURAWSKI, H. -R.;KRUE+, CHEM. BER., 1985, 118, N 8, 3332-3349
作者:SUCROW, W.、MINAS, H.、STEGEMEYER, H.、GESCHWINDER, P.、MURAWSKI, H. -R.、KRUE+