A deprotonation pathway to reactive [B]CH₂ boraalkenes

Abstract

The BH compounds IMes(ArF)BH(NTf2) (ArF: C6F5 or FpXyl) were converted to the IMes(ArF)B=CH2 boraalkenes in a three step reaction sequence of B-methylation with methyllithium, hydride abstraction and deprotonation. The B=CH2...

Bora‐alkenes: Metal Coordination and Reactions with BH‐boranes

“…The structure is similar to that of the copper complex 5 . However, in compound 6 the Au coordination to the B=C unit is more symmetrical; [7a] the difference between the B1−Au1 and C5−Au1 distances amounts to only ca. 0.16 Å (cf.…”

Borataalkenes, boraalkenes, and the η2-B,C coordination mode in coordination chemistry and catalysis

“…Crystallographic evidence for the Z 2 formulation for complexes 4a and 4b include Ta-B distances of 2.728(6) and 2.738(6) Å, and B-C distances of 1.508 (8) and 1.525 (7) The authors note that due to the naturally higher contribution of carbon to the borataalkene's occupied orbitals, ''when there are no d electrons present. .…”

“…The correct assignment of coordination mode in borataalkene complexes is therefore largely dependent on X-ray crystal structure analysis. 5a Besides borataalkenes, several other ligand motifs feature Z 2 -B,C binding, namely boraalkenes, 7,8 arylboranes (ambiphilic ligands) and borylferrocenes (Fig. 3).…”

The BC bond: some recent developments

“…With the AuCl(SMe 2 ) reagent compound 38 reacted to the boraalkene/AuCl π-complex 52 (Scheme 10a). 26 A closely related Rh complex was also characterized by X-ray diffraction. Similarly, the isothiocyanato containing boraalkene 42 formed stable copper, gold, or palladium π-complexes 53 with CuCl, AuCl(SMe 2 ), or [(C 3 H 5 )PdCl] 2 reagents, respectively (Scheme 10a).…”

“…An example is the synthesis of (IMes)(C 6 F 5 )BCH 2 ( 38 , Scheme 7b). 26 It was characterized by an X-ray crystal structure analysis (BC 1.453(5) Å) and it was shown to undergo a variety of cycloaddition reactions ( e.g. with sulfur, carbon dioxide or a reactive ketone) to give cyclic-compounds 39–41 as shown in Scheme 7b.…”