ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
C-Metallated Chiral Alkoxides as d2--and d3 -Regents for the Synthesis of Enantiomerically Pure Compounds (EPC-Synthesis)The chloroalcohols (S)-1 -chloro-2-propanol (1), (S)-1 -chloro-2-methyl-2-pentanol (4), (R)-3-chloro-2-methyl-1 -propanol (7), (R)-4-chloro-2-butanol (10), and (2R, 3R)- 4-chloro-3-methyl-2-butanol (14), really available from the esters of lactic, 3-hydroxy-2-methylpropanoic, and 3-hydroxybutanoic acid are subjected to sequential metallation first with BuLi (or MeMgCl) and then with lithium naphthalenide (or Li metal powder) to give solutions of the highly reactive C -metallated alkoxides 15, 22, 26, 27, and 28, respectively. - These chiral d2- and d3 -reagents may be added to aldehydes (non-diastereoselectively), ketones, and CO2 to give 1, 3- or 1 4-dioles (18-21, 24, 29-33) or δ-lactones (35, 36). Thiolations with dibenzyl disulfide (→ 16, 34) and a deuteration (→ 17, (S)-(1-2H)propan-2-ol) were also carried out. Independent synthesis of (S)-1-benzylthio-2-propanol (16) and comparison of the specific rotations establish that no loss enantiomeric purity occurs on the metallation route. The results described represent and extension of the applicability of simple chiral building blocks to EPC-synthesis.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19840670135
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