ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Diastereoselective Synthesis of Novel Mannich (Bases1) through Titanium ReagentsTrichlorotitanium dialkylamino-alkoxides (2; titanates of N, O-hemiacetals) are generated either from the corresponding lithium alkoxides and titanium tetrachloride (Scheme 1) or by addition of trichloro-dialkuylamino-titanium to aldehydes. The electrophilic (dialkylamino) alkylating reagents 2 are used to convert lithium enolates to β-dialkylamino-ketones and -esters 5 (Mannich bases), see Scheme 2 and Table. One diastereoisomer of the products 5g-5p thus obtained with cyclohexenolate is formed preferentially (66-84%). The configuration of the products of this first diastereoselective version of the Mannich reaction could not yet be determined. A typical procedure for carrying out the reaction is given.
Additional Material:
1 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19840670626
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