Aleksandr Kasatkin

Highly efficient synthesis of propargyl- and allenyltitanium reagents from propargyl halides or propargyl alcohol derivatives. Practical synthesis of allenyl and homopropargyl alcohols

Abstract Reaction of Ti(O-i-Pr) 4 /2 i-PrMgBr, synthetic equivalent of practical Ti(II) reagent, with propargyl halides or propargyl alcohol derivatives affords allenyl titanium compounds in excellent yields, thus providing an efficient and practical method for synthesis of both allenyl and homopropargyl alcohols by the successive treatment with aldehydes or ketones.

Diastereoselective synthesis of trans-1,2-disubstituted cyclopropanols from homoallyl or bis-homoallyl esters via tandem intramolecular nucleophilic acyl substitution and intramolecular carbonyl addition reactions mediated by Ti(OPr-i)4 / 2 i-PrMgBr reagent

Reactions of homoallyl or bis-homoallyl esters with Ti(OPr-i)4/2 i-PrMgBr reagent resulted in intramolecular nucleophilic acyl substitution reaction and successive intramolecular carbonyl addition reaction providing trans-1,2-disubstituted cyclopropanols stereoselectively in excellent yields.

Synthesis of 1-hydroxybicyclo[n.1.0]alkanes (n = 3 and 4) and their silyl ethers from olefinic esters via tandem intramolecular nucleophilic acyl substitution and intramolecular carbonyl addition reactions mediated by Ti(OPr-i)42 i-PrMgCl reagent

Abstract Treatment of olefinic esters with Ti(OPr-i)4/2 i-PrMgCl reagent resulted in intramolecular nucleophilic acyl substitution and successive intramolecular carbonyl addition reactions providing 1-hydroxybicyclo[n.1.0]alkanes (n = 3 and 4) in high yields.

ZIRCONIUM MEDIATED SYNTHESIS. CONVERGENT ACCESS TO TERMINAL TRIENES, DIENES, AND DIENYNES

Abstract Treatment of alkyl, vinyl, or alkynyl zirconocenes with ( E )- or ( Z )-1,4-dichloro-2-butene and 2 equivalents of lithium 2,2,6,6-tetramethylpiperidide gave (3 E )- or (3 Z )-1,3-dienes, 1,3,5-trienes, or 1,3-dien-5-ynes in good yields and stereoselectivity.

Synthesis of chiral allyltitaniums having an amino group at the C-4 position and their diastereoselective addition reaction with aldehydes

Abstract Chiral allyltitaniums having an amino substituent at the C-4 position are prepared from optically active allylic alcohol derivatives 1 and a Ti(O-i-Pr) 4 2i- PrMgCl reagent, which, in turn, react with aldehydes regio- and stereoselectively to afford 3-amino-2-vinylalkanols in excellent yields.

Synthesis of allyltitanium compounds by intramolecular nucleophilic acyl substitution reaction of alka-3,5-dienyl carbonates and their unusual regioselectivity in reaction with aldehydes

Treatment of carbonates of alka-3,5-dien-1-ols with (η2-propene)Ti(OPri)2 resulted in intramolecular nucleophilic acyl substitution (INAS) reaction to afford allyltitanium compounds containing lactone or ester moieties, which add regiospecifically to aldehydes.