Bis(allyl)calcium

Abstract

Bis(allyl)calcium ist erstaunlich beständig und in THF gut löslich. Die Verbindung kristallisiert als Triglyme‐Addukt (siehe Bild; C grau, O rot). Die Umsetzung mit Iod ergibt unter selektiver C‐C‐Kupplung 1,5‐Hexadien.

Calcium‐Mediated Dearomatization, CH Bond Activation, and Allylation of Alkylated and Benzannulated Pyridine Derivatives

“…[23] The previously reported compound bisA C H T U N G T R E N N U N G (allyl)calcium (1) [24] undergoes rapid 1,2-insertion of pyridine and subsequent rearrangement to give the 1,4-carbometalated product (Scheme 1). [25] By this procedure, an allyl moiety can easily be attached to the C 5 H 5 N ring, without the need for an activating or protecting group.…”

“…The bond lengths of 2.846(3) (Ca1-C6) and 2.813(3) (Ca1-C13) lie in the range of calcium-carbon bonds observed for the triglyme adduct of bisA C H T U N G T R E N N U N G (h 3 -allyl)calcium and exclude s-bound carbanionic ligands. [24] The Ca1-N1 and Ca1-N2 bond lengths of 2.407(2) and 2.4331 (19) are somewhat longer than those in 9 a·A C H T U N G T R E N N U N G (THF) 4 …”

Insertion of Pyridine into the Calcium Allyl Bond: Regioselective 1,4‐Dihydropyridine Formation and CH Bond Activation

“…Herein we show that the recently introduced organocalcium complex bis(allyl)calcium (1) [11] selectively transfers its allyl groups to pyridine (py) to give 4-allyl-1,4-DHP, whereas the C À H bond of ortho-and para-methyl groups in picolines and lutidines are metalated only under thermodynamic control.…”

Ein kationischer Calciumhydridcluster, stabilisiert durch einen von Cyclen abgeleiteten makrocyclischen N,N,N,N‐Liganden

“…[7] Die Ca-H-Bindungslängen in 3 b und 3 c zeigen grçßere Differenzen (2.03(8) bis 2.50 (9) ), was zu einem durchschnittlichen Abstand Ca-H av von 2.33 (9) führt. [7] Die Ca-H-Bindungslängen in 3 b und 3 c zeigen grçßere Differenzen (2.03(8) bis 2.50 (9) ), was zu einem durchschnittlichen Abstand Ca-H av von 2.33 (9) führt.…”