Some reactions of hexafluorobutyne-2 with phosphines and amines

Abstract

The addition reaction R2EX + CF3C≡CCF3 → R2EC(CF3)=C(CF3)X has been investigated further (E = P and N); 1:1 adducts have been obtained from (C2H5)2PH, (CF3)2PH, (C6H5)2P—P(C6H5)2, and (CH3)2NCl, but not from (CH3)2PCl or (CH3)2P—P(CH3)2. (CF3)2PH also gives a 2:1 adduct. Triphenylphosphine causes the butyne to polymerize at − 78°. A similar but slower reaction takes place with trimethylamine. In the presence of water, trimethylamine and the butyne give the bis(butenyl) ether cis,trans (CF3CH=CCF3)2O as the major product.

Metal‐Assisted, Reversible Phosphinyl Phosphination of the Carbon–Nitrogen Triple Bond in a Nitrile

“…The largest progress has been made in the field of O,O and N,N ligands, for which protocols for stereo‐ and even enantioselective dihydroxylation1 or diamination of olefins2 have been worked out. Viable approaches to P,P‐donor ligands, which are likewise of great significance, by diphosphination of organic precursors have been found in the double metathesis of 1,2‐disubstituted olefins,3 or in the addition of the PP bonds of diphosphines to alkenes4 or alkynes 5. 6…”

Stereoselective addition of diphenylphosphine to substituted diphenylethynes: synthetic, NMR and X-ray crystallographic studies

“…but it is known that the alkynes with more electronwithdrawing substituents MeO 2 CC᎐ ᎐ ᎐ CCO 2 Me and F 3 CC᎐ ᎐ ᎐ CCF 3 can undergo double addition reactions of this sort, probably under radical conditions, to give diphosphines in each case. [13][14][15][16] The behaviour found here is summarised in Scheme 3 in which X is assumed to be bulkier than Y. Initial nucleophilic Michaellike attack by Ph 2 P Ϫ is on the ethynic carbon atom which carries the least bulky substituent as in (i) (syn) or (iii) (anti).…”

Pyrazolyl-bridged iridium dimers. 8. Two-center, electrophilic addition of activated acetylenes to bis(cycloocta-1,5-diene)bis(.mu.-pyrazolyl)diiridium(I) leading to a diiridacyclobutene configuration: regular, parallel coordination of methyl propiolate

“…1765 ( 14) 8901 ( 20) 64 ( 8) 0(23) -2366 ( 18) 2300 ( 14) 9327 ( 21) 67 (8) 0(24) -2460 ( 16) 3467 ( 16) 8938 ( 18) 66 ( 8) 0(25) -1812 ( 14) 3765 ( 14) 7785 ( 18) 55 ( 7) 0(26) -2192 ( 17) 3230 ( 15) 6391 ( 18) 62 ( 8) 0(27) -3357 ( 18) 2196 ( 16) 5778 ( 21) 80 ( 9) 0(28) -2883 ( 18) 1155 ( 15) 6115 ( 20) 72 ( 8)…”