Synthesis and stereoselective halogenolysis of optically pure benzylstannanes.
In this work we show that lithium ortho-sulfinyl benzylcarbanions are highly efficient reagents for the synthesis of optically pure benzylstannanes by reacting with halotriorganyl tin (up to >98:2 dr). The stereoselectivity of these reactions is opposite to those observed with carbon electrophiles. Bromolysis of the obtained ortho-sulfinylbenzylstannanes with Br(2) in the presence of CuBr takes place in a highly stereoselective way (up to 90:10 dr) with retention of the configuration, which allows the synthesis of optically pure 2-sulfinylated benzyl bromides. Different experiments support the proposed mechanistic rationalization for both processes.
García Ruano
José L
JL
Departamento de Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco 28049 Madrid, Spain. joseluis.garcia.ruano@uam.es
Alemán
José
J
Parra
Alejandro
A
Alcudia
Ana
A
Maya
Celia
C
D018360:Crystallography, X-Ray; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D017971:Tin Compounds / Q000737:chemistry*
D009942:Organometallic Compounds; D017971:Tin Compounds; C031525:stannane