Syntheses and Palladium, Platinum, and Borane Adducts of Symmetrical Trialkylphosphines with Three Terminal Vinyl Groups, P((CH₂)_mCH=CH₂)₃

Abstract

Reactions of Br(CH2)mCH=CH2 with Mg powder and then PCl3 (0.33 equiv.) afford P((CH2)m- CH=CH2)3 (1; m = a, 4; b, 5; c, 6; d, 7; e, 8; f, 9; 52 - 87%). Reactions of 1a - c, e with PdX2(COD) (X = Cl, Br) give trans-PdX2(P((CH2)mCH=CH2)3)2 (35 - 92%). Reactions of 1b - e with PtCl2 in benzene give mainly trans-PtCl2(P((CH2)mCH=CH2)3)2 (trans-5b-e; 52 - 75%), whereas those with K2PtCl4 in water give mainly cis-5b-e (33 - 70%). The reaction of equimolar quantities of 1c and H3B・S(CH3)2 gives the 1 : 1 adduct H3B・P((CH2)6CH=CH2)3 (85%). In none of these transformations are by-products derived from the C=C linkages observed

Gyroscope‐Like Molecules Consisting of PdX2/PtX2 Rotators within Three‐Spoke Dibridgehead Diphosphine Stators: Syntheses, Substitution Reactions, Structures, and Dynamic Properties

“…Platinum and palladium dichloride complexes of the formula trans ‐[MCl 2 (P{(CH 2 ) m CHCH 2 } 3 ) 2 ] ( m =4–8) were prepared by routine procedures described previously 19. [Note that the notation a – e in the compounds numbers given hereafter, refer to m =4–8, respectively.]…”

“…Metathesis/hydrogenation sequences were also conducted with analogous palladium dibromide complexes 19. With trans ‐ 3 a , b , which feature four or five methylene groups in each phosphine substituent, oligomers or polymers were again obtained (Scheme , bottom).…”

“…Method A : A two‐necked flask was charged with trans – 1 d 19 (0.522 g, 0.484 mmol) and CH 2 Cl 2 (250 mL; the resulting solution was 0.0019 M in trans ‐ 1 d ), and fitted with a condenser with a bubbler. The solution was cooled to 0 °C.…”

Gyroscope like molecules consisting of trigonal or square planar osmium rotators within three-spoked dibridgehead diphosphine stators: syntheses, substitution reactions, structures, and dynamic properties

“…17 Accordingly, the hexachloride and hexabromide complexes (NH 4 ) 2 OsX 6 15 were suspended in 2-methoxyethanol and heated under CO (10 bar) to give light yellow solutions. Subsequent additions of the alkene containing phosphines P((CH 2 ) m CHvCH 2 ) 3 (m = 6, 1a; 7, 1b; 8, 1c) 18 gave, as depicted in Scheme 2, the bis( phosphine) complexes cis,cis,transOs(CO) 2 (X) 2 (P((CH 2 ) m CHvCH 2 ) 3 ) 2 (X = Cl, 2a-c; X = Br, 3a-c) as yellow oils in 46-73% yields after chromatographic workups. 19 All new complexes were characterized by NMR ( 1 H, 13 C{ 1 H}, 31 P{ 1 H}) and IR spectroscopy, mass spectrometry, and microanalysis, as summarized in the ESI.…”

Dibridgehead Diphosphines that Turn Themselves Inside Out

“…Chromatographic separation on silica gel gave the bis(borane) adducts (in,in/out,out)-2·2 BH 3 as a slowly solidifying oil and in,out-2·2BH 3 as a colorless viscous liquid in yields of 43 and 42 %, respectively. In a second route, the phosphine borane H 3 B·P((CH 2 ) 6 CH = CH 2 ) 3 [18] was treated with the Grubbs catalyst. Such an alkene metathesis would be expected to yield much oligomer, polymer, and other byproducts.…”