Synthese und Charakterisierung neuer Se‐ und S‐haltiger Bor‐Heterocyclen: 2,3‐Dihydro‐1,2,3‐selenazaborole und 3 H ‐2,1,3‐Thiaselenaborole

Abstract

3-Alkyl-3H-1,2,3-diselenaborole 1 reagieren rnit Schwefeldiimiden unter Bildung der bisher unbekannten 3-Alkyl-2,3-dihydro-1,2,3-selenazaborole 2. Die unerwartete Substitution des Bor-standigen Stickstoffs durch Schwefel fiihrt zu den 3-Alkyl-3H-2,1,3-Thiaselenaborolen 3. Die 'H-, I'B-, "C-, "N-, 29Si-, "Se-NMR-und Massenspektren werden diskutiert.Aus 3H-1,2,3-Diselenaborolen 1 (R = CH3, n-C4H9) und organischen Isocyanaten sind 2,3-Dihydro-4H-1,3,2-selenazaborin-4-one ' ) zuganglich, in denen die Elemente Selen und Stickstoff iiber Bor gebunden vorliegen. 3-alkyl-3N-2,1,3-thiaboroles 3. The IH-, I'B-, I3C-, l5N-, 29Si-, 77Se-NMR, and mass spectra are discussed.

Selective Consecutive Insertion of Alkynes into the B–Se Bonds of 1,3,2‐Diselenaborolane Derivatives: Synthesis and Molecular Structures of Nine‐Membered Rings

“…Although some applications of noncyclic selenoboranes1,2 have been described,3 their cyclic analogues appear to be even more intriguing due to their potential use in heterocyclic synthesis4,5 or as ligands for transition‐metal complexes 6. Theformer has been shown by the conversion of 1,3,4,2,5‐triselenaborolanes into novel ring systems through reactions with isocyanates5a or alkynes 5b,5c. Recently, we prepared the first stable 1,3,2‐diselenaborolane derivatives 2 (Scheme )7 starting from the silane 1 8 through exchange reactions.…”