Q.-L. Zhao et al. / Tetrahedron: Asymmetry 18 (2007) 1899–1905
1903
24.7, 25.3, 25.6, 33.9, 35.2, 35.6, 36.7, 64.0, 66.3, 72.7, 75.0,
4.5. 1,2:5,6-Di-O-cyclohexylidene-3-[(3,5-dimethyl)phenyl-
77.0, 77.3, 77.5, 109.0, 110.6, 113.3, 118.0, 118.4, 122.1,
122.8, 123.7, 124.0, 124.5, 124.6, 124.9, 125.6, 126.6,
127.0, 127.1, 127.7, 128.0, 128.9, 129.0, 129.3, 129.5,
130.0, 130.6, 131.6, 132.8, 133.1, 133.8, 152.6 ppm.
carbamate]-4-[(S)-1,10-binaphthyl-2,20-diyl]phosphite-D-
mannitol 4a and 1,2:5,6-di-O-cyclohexylidene-3-[(3,5-
dimethyl)phenylcarbamate]-4-[(R)-1,10-binaphthyl-2,20-
diyl]phosphite-D-mannitol 4b
Treatment of the in situ formed12 (R)-1,10-binaphthyl-2,20-
diyl-chlorophosphine (0.87 mmol) and compound 5a affor-
ded ligand 2b, which was purified by flash chromatography
(CH2Cl2/Et2O, 9/1, Rf = 0.84) to produce a white powder
(0.28 g, 46%). 31P NMR (202 MHz, CDCl3), d =
156.1 ppm. 1H NMR (CDCl3): d = 1.17–1.83 (m, 20H),
3.71 (s, 1H), 3.87 (s, 1H), 3.93 (s, 1H), 4.08 (s, 1H), 4.18
(d, J = 6.5 Hz, 1H), 4.31 (s, 1H), 4.90 (d, J = 7.5 Hz,
1H), 5.01 (d, J = 7.0 Hz, 1H), 6.51 (s, NH), 6.94–7.84 (m,
17H, Ar-H) ppm. 13C NMR (125 MHz, CDCl3): d =
24.0, 24.2, 24.3, 25.5, 25.6, 34.0, 35.2, 35.9, 36.8, 64.1,
66.9, 72.9, 75.6, 77.1, 77.3, 77.6, 110.0, 110.6, 111.3,
118.1, 118.8, 122.0, 122.3, 123.2, 124.3, 124.5, 124.6,
124.7, 125.6, 126.6, 127.2, 127.3, 127.7, 128.5, 128.6,
129.1, 129.3, 129.7, 130.2, 130.6, 131.8, 132.9, 133.1,
133.7, 152.3 ppm.
(S)-1,10-Binaphthyl-2,20-diyl-chlorophosphine (0.87 mmol)
was synthesized in situ12 and dissolved in toluene
(10 mL). Compound 5c (0.381 g, 0.8 mmol) was azeotropi-
cally dried with toluene (3 · 10 mL) and then dissolved in
triethylamine (4 mL) to which DMAP (0.01 g, 0.083 mmol)
had been added. A solution of phosphorochloridite was
transferred slowly to a solution of compound 5c at 0 ꢁC.
The reaction mixture was stirred overnight at room tem-
perature, and the formed triethylamine salts were removed
by filtration. Evaporation of the solvent gave a white foam,
which was purified by flash chromatography (CH2Cl2/
Et2O, 9/1, Rf = 0.86) to produce 4a as a white powder
(0.42 g, 66%). 31P NMR (202 MHz, CDCl3), d =
153.7 ppm. 1H NMR (CDCl3): d = 1.61–1.86 (m, 20H),
2.30 (s, 6H), 3.94–4.14 (m, 3H), 4.29 (s, 2H), 4.53 (d,
J = 7.0 Hz, 1H), 4.92 (s, 1H), 5.22 (d, J = 7.5 Hz, 1H),
6.74 (s, NH), 7.01–8.02 (m, 15H, Ar-H) ppm. 13C NMR
(125 MHz, CDCl3): d = 21.6, 21.7, 24.0, 24.3, 25.5, 33.9,
35.3, 35.9, 36.8, 64.1, 66.9, 72.9, 74.3, 75.1, 75.6, 77.1,
77.3, 77.6, 110.0, 110.6, 116.6, 122.0, 122.3, 123.2, 124.7,
125.3, 125.6, 125.9, 126.3, 126.5, 127.3, 128.5, 128.6,
129.3, 130.2, 130.6, 131.4, 131.8, 132.9, 133.1, 137.3,
138.1, 139.1, 147.3, 147.6, 148.6, 152.3 ppm.
4.4. 1,2:5,6-Di-O-cyclohexylidene-3-[(4-methylphenylcarba-
mate)]-4-[(S)-1,10-binaphthyl-2,20-diyl]phosphite-D-mannitol
3a and 1,2:5,6-di-O-cyclohexylidene-3-[(4-methylphenylcar-
bamate)-4-[(R)-1,10-binaphthyl-2,20-diyl]phosphite-D-manni-
tol 3b
Treatment of the in situ formed12 (S)-1,10-binaphthyl-2,20-
diyl-chlorophosphine (0.87 mmol) and compound 5b affor-
ded ligand 3a, which was purified by flash chromatography
(CH2Cl2/Et2O, 9/1, Rf = 0.85) to produce a white powder
(0.25 g, 40%). 31P NMR (202 MHz, CDCl3), d =
154.5 ppm. 1H NMR (CDCl3): d = 1.32–1.74 (m, 20H),
2.23 (s, 3H), 3.86 (m, 1H), 3.95 (m, 1H), 4.13 (m, 3H),
4.40 (d, J = 6.0 Hz, 1H), 4.78 (d, J = 12.5 Hz, 1H), 5.08
(d, J = 7.0 Hz, 1H), 6.49 (s, NH), 6.91–7.91 (m, 16H, Ar-
H) ppm. 13C NMR (125 MHz, CDCl3): d = 21.5, 23.9,
24.3, 25.6, 33.0, 35.5, 35.8, 36.6, 64.7, 65.9, 71.9, 76.6,
76.9, 77.0, 77.9, 109.0, 110.8, 117.9, 121.0, 122.1, 122.2,
123.2, 124.6, 124.7, 125.0, 125.1, 125.3, 126.3, 126.5,
127.0, 127.2, 128.3, 128.6, 129.8, 130.1, 130.5, 131.2,
131.8, 132.9, 133.1, 133.6, 134.8, 147.6, 148.3, 148.6,
151.3 ppm.
Treatment of the in situ formed12 (R)-1,10-binaphthyl-2,20-
diyl-chlorophosphine (0.87 mmol) and compound 5c affor-
ded ligand 4b, which was purified by flash chromatography
(CH2Cl2/Et2O, 9/1, Rf = 0.87) to produce a white powder
(0.30 g, 47%). 31P NMR (202 MHz, CDCl3), d =
156.6 ppm. 1H NMR (CDCl3): d = 1.32–1.71 (m, 20H),
2.31 (s, 6H), 3.87 (s, 1H), 4.08 (d, J = 22 Hz, 2H), 4.23
(s, 1H), 4.34 (d, J = 4.5 Hz, 1H), 4.46 (s, 1H), 5.06 (d,
J = 7.0 Hz, 1H), 5.15 (d, J = 6.5 Hz, 1H), 6.56 (s, NH),
6.75–8.01 (m, 15 H, Ar-H) ppm. 13C NMR (125 MHz,
CDCl3): d = 21.0, 21.7, 24.0, 24.3, 26.5, 33.9, 35.3, 36.8,
64.1, 66.9, 73.9, 74.3, 75.1, 75.3, 75.9, 77.1, 77.3, 77.6,
110.0, 110.6, 116.6, 122.0, 122.8, 123.2, 124.7, 125.1,
125.3, 125.6, 125.9, 126.4, 126.5, 127.3, 128.5, 128.6,
129.3, 130.2, 130.6, 131.1, 131.8, 132.9, 133.1, 137.3,
138.1, 139.1, 147.2, 147.6, 148.9 ppm.
Treatment of the in situ formed12 (R)-1,10-binaphthyl-2,20-
diyl-chlorophosphine (0.87 mmol) and compound 5b affor-
ded ligand 3b, which was purified by flash chromatography
(CH2Cl2/Et2O, 9/1, Rf = 0.83) to produce a white powder
(0.27 g, 43%). 31P NMR (202 MHz, CDCl3), d =
157.6 ppm. 1H NMR (CDCl3): d = 1.33–1.84 (m, 20H),
2.20 (s, 3H), 3.73 (s, 1H), 3.94 (m, 2H), 4.07 (m, 1H),
4.18 (d, J = 8.0 Hz, 1H), 4.32 (s, 1H), 4.91 (d, J =
7.5 Hz, 1H), 5.01 (d, J = 6.5 Hz, 1H), 6.46 (s, NH), 6.99–
7.88 (m, 16H, Ar-H) ppm. 13C NMR (125 MHz, CDCl3):
d = 21.0, 24.0, 24.3, 25.5, 33.9, 35.2, 35.9, 36.7, 64.0,
66.9, 72.9, 75.6, 77.0, 77.3, 77.5, 109.9, 110.5, 118.9,
122.0, 122.1, 122.2, 123.1, 124.6, 124.7, 125.0, 125.1,
125.3, 126.2, 126.5, 127.2, 127.3, 128.5, 128.6, 129.8,
130.2, 130.5, 131.4, 131.8, 132.9, 133.1, 133.7, 134.9,
147.6, 148.5, 148.6, 150.8 ppm.
4.6. 1,2:5,6-Di-O-cyclohexylidene-3,4-bis[(S)-1,10-binaph-
thyl-2,20-diyl]phosphite-D-mannitol 6a and 1,2:5,6-di-O-
cyclohexylidene-3,4-bis[(R)-1,10-binaphthyl-2,20-diyl]phos-
phite-D-mannitol 6b
Compound 1 (0.206 g, 0.6 mmol) and DMAP (0.015 g,
0.123 mmol) were put in a 50 mL round-bottomed flask.
Toluene (5 mL) and dry triethylamine (0.2 mL) were added
under dry nitrogen. The mixture was cooled to 0 ꢁC. with
an ice-bath. (S)-1,10-Binaphthyl-2,20-diyl-chlorophosphine
(1.2 mmol) synthesized in situ12 in toluene (5 mL) was
added dropwise in the solution and stirred for 30 min at
0 ꢁC, then left at room temperature overnight. The solvent
was removed in vacuo and the residues were purified by
flash chromatography (toluene, Rf = 0.33) to produce 6a