Transient Dipnictyl Analogues of Acrylamides, R−E=E′−CONR₂, and a Related Diphosphadigalletane from Na[OCP] and (R₂N)₂ECl (E, E′=P, As, Ga)

Abstract

The reaction of Na[OCP] with (R2N)2ECl (E=P or As; R=alkyl) granted direct access to transient amine‐substituted diphospha‐ and arsaphospha‐acrylamide analogues, (R2N)E=P(CONR2) 1. Their facile formation allowed for a comprehensive reactivity study. Dimerization yielded the four‐membered rings (R2N)2E2P2(CONR2)2, whereas in the presence of excess Na[OCP], a stepwise [2+2] cycloaddition occured, leading to the sodium salts of carboxotripnictides [(R2N)EP2CO(CONR2)]−. These salts served as a reservoir of 1, either by extrusion of Na[OCP] or by reaction with the appropriate (R2N)2ECl, giving the [4+2]‐cycloaddition products (R2N)EP(C6H10)(CONR2) in the presence of 2,3‐dimethylbutadiene. The formal conjugate addition product K[(tBuO)(R2N)PP(CONR2)] was obtained by reaction of Na[(R2N)PP2CO(CONR2)] with tBuOK. In addition, a rare diphosphadigalletane with a ladder‐type (R2N)2Ga2P2(CONR2)2 core was isolated from the reaction of Na[OCP] with (R2N)2GaCl (R=alkyl). The unprecedented pnictogenyl carboxamide compounds were thoroughly characterized, including single‐crystal X‐ray structure determinations, and mechanisms for their formation were investigated by DFT calculations.

Heavy Chains: Synthesis, Reactivity and Decomposition of Interpnictogen Chains with Terminal Diaryl Bismuth Fragments

“…In compound 4 Ph The Bi−P distance is 262.40(7) pm and fits well to the bond lengths in 1 Ph (261.86(6) and 266.26(8) pm) and the other previously mentioned reference compounds [1,3,10,13,20,21] . The As−P bond has a length of 235.40(7) pm, which is in the usual range for covalent As−P single bonds [4,5,29–31] . The Bi−P−As angle around the central phosphorus atom is 113.58(3)°, much larger than the angle around the central P atom in compound 1 Ph (90.05(3))°.…”

“…[ 1 , 3 , 10 , 13 , 20 , 21 ] The As−P bond has a length of 235.40(7) pm, which is in the usual range for covalent As−P single bonds. [ 4 , 5 , 29 , 30 , 31 ] The Bi−P−As angle around the central phosphorus atom is 113.58(3)°, much larger than the angle around the central P atom in compound 1 Ph (90.05(3))°.…”

Insertion of CS2 into a Phosphorus–Arsenic Single Bond and Investigations on Phosphane Arsanyldithiocarboxylates

“…26 Gruẗzmacher and co-workers reported on species D (Scheme 1), which was accessed by the reaction of Na [OCP] with the secondary chloroarsane (iPr 2 )N 2 AsCl and further conversion of the intermediate species with dimethylbutadiene. 27 However, the reactivity of compounds containing single bonds between unlike pnictogen atoms is by far less investigated than the reactivity of the homonuclear derivatives. Goicoechea et al recently reported on the synthesis and reactivity of the (arsino)phosphaketene As(PCO){[N(Dipp)]-(CH 2 )} 2 (Scheme 1, B), which shows an interesting reactivity toward B(C 6 F 5 ) 3 , resulting in the formation of a cyclic cisarsaphosphene.…”

Deciphering the Differences in Ambident Reactivity between the Cyanate, Thiocyanate Ions, and their P‐ and As‐Containing Analogues

“…Indeed, the P-and Ge-centred electrophiles led to the clean formation of the phosphaketene isomers RÀ P=C=O (similar to the C-electrophiles, see above). [56,[120][121][122] As for R: Me 2 Al, the phosphaalkyne (RÀ OÀ C�P) isomer was accessed using diisobutylaluminum chloride, [123] and our calculations predict only negligible difference between the stabilities of the two isomers. The ΔΔG 0 values for R: Me 3 Si or Me 2 B groups are also close to zero, indicating very similar stabilities of the two possible isomers.…”