Beilstein J. Org. Chem. 2018, 14, 2354–2365.
sulting solution was 0.0097 M in 1·BH3) and cooled to 0 °C. A (EI) [56]: 340 ([M − BH3]+, 93%), 228 ([M − BH3 − C8H17 +
solution of Grubbs' first generation catalyst (0.077 g, 1]+, 100%).
0
.094 mmol, 3 mol %) in CH2Cl2 (50 mL) was added dropwise
via syringe with stirring over 1 h. The cooling bath was re- in,out-H3B·P((CH2)14)3P·BH3 (in,out-2·2BH3; 039 g,
moved. After 2 h, additional Grubbs' first generation catalyst 0.057 mmol, 4%), colorless oil. Anal. calcd for C42H90B2P2
was added as a solid (0.051 g, 0.062 mmol, 2 mol %). The flask (678.73): C, 74.32; H, 13.37; found: C, 73.86; H, 13.49;
was fitted with a condenser and the mixture was refluxed 1H NMR (500 MHz, CDCl3) δ 1.56–1.51 (m, 12H, PCH2),
overnight, cooled to room temperature, and passed through a 1.49–1.42 (m, 12H, CH2), 1.39–1.33 (m, 12H, CH2), 1.31–1.21
SiO2 pad (3 cm), which was rinsed with CH2Cl2. The eluate (m, 48H, CH2), 0.45 and 0.27 (br apparent d, 6H, BH3);
was concentrated to ca. 20 mL by rotary evaporation, and trans- 13C{1H} NMR (126 MHz, CDCl3) δ 30.5 (d, JCP = 11.3 Hz,
ferred to a Fischer–Porter bottle. Wilkinson's catalyst (0.086 g, CH2), 28.35 (s, CH2), 28.28 (s, CH2), 28.2 (s, CH2), 28.1 (s,
0
.093 mmol, 3 mol %) was added, and the bottle was partially CH2), 23.0 (d, JCP = 34.3 Hz, CH2), 22.2 (d, JCP = 1.9 Hz,
evacuated and charged with hydrogen (5 bar). The sample was CH2); 31P{1H} NMR (202 MHz, CDCl3) δ 15.6 and 15.4 (br
kept at 55 ºC for 60 h. The solvent was removed and the residue apparent d); IR (oil film): 2926 (s), 2853 (m), 2366 (w), 1459
3
1
.5 × 36 cm), which was eluted with hexanes/CH2Cl2 (3:1 to (MALDI+, THAP) [56]: 651.6 ([M – 2BH3 + 1]+, 100%).
:3 v/v) and then CH2Cl2. Fractions were assayed by TLC,
combined where appropriate, and slowly evaporated to dryness
(6·2BH3;
in a fume hood. Some fractions (0.091 g total out of the recov- 0.101 g, 0.149 mmol, 10%), white solid, mp 96 °C (capillary).
ered mass of 0.344 g) consisted of unidentified and/or impure Anal. calcd for C42H90B2P2 (678.73): C, 74.32; H, 13.37;
products, or oligomers and polymers. Products that could be found: C, 73.92; H, 13.47. The identity of this compound,
characterized are as follows (in order of elution).
crystallographically [6]. 1H NMR (500 MHz, CDCl3)
H3B·P(n-C8H17)3 (4·BH3 [33]; 0.007 g, 0.018 mmol, 1%), δ 1.65–1.14 (br m, 84H, CH2), 0.49 and 0.26 (br apparent d,
colorless oil. Anal. calcd for C24H54BP (384.47): C, 74.98; H, 6H, BH3); 13C{1H} NMR (126 MHz, CDCl3) δ 31.3 (d,
1
4.16; found: C, 74.93; H, 14.02; 1H NMR (400 MHz, CDCl3) JCP = 12.6 Hz, CH2), 29.54 (s, CH2), 29.53 (s, CH2), 29.4 (s,
δ 1.53–1.37 (m, 12H, CH2), 1.33–1.30 (m, 6H, CH2), 1.26–1.23 CH2), 29.1 (s, CH2), 29.0 (d, JCP = 11.1 Hz, 2CH2), 26.8 (s,
(
(
m, 24H, CH2), 0.83 (t, 3JHH = 6.9 Hz, 9H, CH3), 0.47 and 0.19 2CH2), 26.6 (s, 2CH2), 26.5 (s, 2CH2), 26.1 (s, 2CH2), 23.8 (d,
br apparent d, 3H, BH3); 13C{1H} NMR (101 MHz, CDCl3) JCP = 35.3 Hz, CH2), 22.6 (d, JCP = 1.0 Hz, CH2), 22.3 (d,
δ 31.7 (s, CH2), 31.1 (d, JCP = 12.0 Hz, CH2), 29.0 (s, CH2), JCP = 33.5 Hz, 2CH2), 21.2 (d, JCP = 3.3 Hz, 2CH2);
2
2
8.9 (s, CH2), 22.9 (d, JCP = 34.3 Hz, CH2), 22.50 (s, CH2), 31P {1H} NMR (202 MHz, CDCl3) δ 15.6 and 15.2 (br apparent
2.48 (s, CH2), 14.0 (s, CH3); 31P{1H} NMR (162 MHz, d); IR (powder film): 2922 (s), 2853 (m), 2366 (m), 1459 (m),
2
856 (m), 2366 (m), 1463 (m), 1413 (w), 1378 (w), 1135 (w), [56]: 678 (M+, 9%), 665 ([M − BH3]+, 100%), 652 ([M − 2BH3
56]: 384 (M+, <1%), 370 ([M − BH3]+, 79%).
(
in,in/out,out)-H3B·P((CH2)14)3P·BH3 ((in,in/out,out)-2·2BH3;
(
5·BH3; 0.090 g, 0.25 mmol, 0.016 g, 0.024 mmol, 2%), colorless oil that solidified to give a
8
7
%), colorless oil. Anal. calcd for C22H48BP (354.40): C, white powder, mp 112 °C. Anal. calcd for C42H90B2P2
4.56; H, 13.65; found: C, 74.27; H, 13.52; 1H NMR (678.73): C, 74.32; H, 13.37; found: C, 74.71; H, 13.34;
(
500 MHz, CDCl3) δ 1.62–1.19 (m, 42H, CH2), 0.86 (t, 3H, 1H NMR (500 MHz, CDCl3) δ 1.55–1.50 (m, 12H, CH2),
3
1
JHH = 7.0 Hz, CH3), 0.48 and 0.26 (br apparent d, 3H, BH3); 1.47–1.39 (m, 12H, CH2), 1.37–1.32 (m, 12H, CH2), 1.29–1.21
3C{1H} NMR (126 MHz, CDCl3) δ 31.7 (s, CH2), 31.2 (d, (m, 48H, CH2), 0.38 and 0.26 (br apparent d, 6H, BH3);
JCP = 12.6 Hz, CH2), 29.03 (s, CH2), 29.01 (s, CH2), 28.9 (d, 13C{1H} NMR (126 MHz, CDCl3) δ 30.6 (d, JCP = 12.1 Hz,
JCP = 11.1 Hz, 2CH2), 26.7 (s, 2CH2), 26.53 (s, 2CH2), 26.48 CH2), 29.23 (s, CH2), 29.17 (s, CH2), 28.9 (s, CH2), 28.4 (s,
(
(
s, 2CH2), 26.1 (s, 2CH2), 23.8 (d, JCP = 35.4 Hz, CH2), 22.57 CH2), 22.5 (d, JCP = 34.1 Hz, CH2), 22.1 (d, JCP = 2.7 Hz,
d, JCP = 1.2 Hz, 2CH2), 22.55 (s, CH2), 22.3 (d, JCP = 33.6 Hz, CH2); 31P{1H} NMR (202 MHz, CDCl3) δ 14.9 and 14.7 (br
CH2), 21.2 (d, JCP = 3.3 Hz, 2CH2), 14.0 (s, CH3); apparent d); IR (powder film): 2922 (s), 2853 (s), 2366 (m),
d); IR (oil film): 2926 (s), 2856 (m), 2366 (m), 1459 (m), 1417 (m) cm−1; MS (MALDI+, THAP) [56]: 702.0 ([M + Na]+,
w), 1135 (w), 1061 (m), 811 (m), 760 (m), 722 (m) cm−1; MS 98%), 666.0 ([M − BH3 + 1]+, 100%).
3
(
2363