5-Exo-dig aminocylization/hydroxyfluorination of propargylic carbamates

Article abstract of DOI:10.1016/j.jfluchem.2018.04.002

The unprecedented annulation/hydroxyfluorination of propargylic carbamates to give 4-fluoromethyl-4-hydroxy-oxazolidinones was investigated. The reaction was effectively promoted by NaHCO₃ and/or silver catalysis. The peculiar behavior of propa

Full text of DOI:10.1016/j.jfluchem.2018.04.002

Accepted Manuscript
Title: 5-Exo-dig Aminocylization/Hydroxyfluorination of
Propargylic Carbamates
Authors: Antonio Arcadi, Marco Chiarini, Luana Del Vecchio,
Fabio Marinelli
PII:
S0022-1139(18)30092-7
DOI:
Reference:
https://doi.org/10.1016/j.jfluchem.2018.04.002
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3-4-2018
Please cite this article as: Arcadi A, Chiarini M, Del Vecchio L, Marinelli F, 5-Exo-dig
Aminocylization/Hydroxyfluorination of Propargylic Carbamates, Journal of Fluorine
Chemistry (2010), https://doi.org/10.1016/j.jfluchem.2018.04.002
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5-Exo-dig Aminocylization/Hydroxyfluorination of Propargylic Carbamates
Antonio Arcadi a,*, Marco Chiarini b, Luana Del Vecchio a, and Fabio Marinelli a,*
a Dipartimento di Scienze Fisiche e Chimiche Università degli Studi di L’Aquila; Via Vetoio, 67100 Coppito (AQ), Italy
b Facoltà di Bioscienze e Tecnologie Agro-Alimentari e Ambientali, Università degli Studi di Teramo; Via R. Balzarini 1,
64100 Teramo (TE), Italy
Antonio Arcadi e-mail: antonio.arcadi@univaq.it
Fabio Marinelli e-mail: fabio.marinelli@univaq.it
GRAPHICAL ABSTRACT
Highlights:


Annulation/hydroxyfluorination of propargylic carbamates was investigated.
An efficient approach to the synthesis of 4-fluoromethyl-4-hydroxy-oxazolidinones
is reported.


Diastereomeric enriched fluorohydroxy-oxazolidinones were isolated.
Steroidal propargylic carbamates led to the formation of -fluoroketone derivatives
by a ring opening reaction of flurohydroxyoxazolidinones.
Keywords
Propargylic carbamates; Sequential reactions; Annulation; Hydroxyfluorination; 4-Fluoromethyl-4-hydroxy-
oxazolidinones.
Abstract

The unprecedented annulation/hydroxyfluorination of propargylic carbamates to give 4-fluoromethyl-4-
hydroxy-oxazolidinones was investigated. The reaction was effectively promoted by NaHCO3 and/or silver
catalysis. The peculiar behavior of propargylic carbamates bearing a chiral steroidal moiety is described.
Extensions and limitations of the procedure with respect to urea derivatives, homopropargyl compounds,
internal alkynes and one-pot transformations of propargylic alcohols with isocyanates are reported.
1. Introduction
The key role of fluorinated substances in a wide range of applications [1,2] in academia and industry is spurring
on the development of efficient introduction methods of fluorine into organic compounds [3-28]. Usually,
fluorinated substituents can accomplish significant modulation of molecular properties of pharmaceuticals and
bioactive substances such as solubility, bioavailability, metabolic stability and binding affinity to target proteins
[29]. Many synthetic strategies have been developed for the fluorination [3-28], among them the combination
of cyclization and fluorination reaction in a single operation provides a powerful tool to assemble fluorinated
heterocycles from unsaturated compounds bearing a close heteroatom nucleophile. Various metal-catalyzed
intramolecular aminofluorination [30-34] and oxyfluorination reactions [35-44] of alkenes [45-47] or their metal-
free alternative [48,49] have been developed. The cycloisomerization/fluorination sequence of alkynes is
emerging as an attractive, and step- economic, tool to access fluorinated heterocyclic derivatives [50-58]. As
part of our ongoing interest in the development of efficient methodologies for the selective preparation of
fluorinated compounds [59,60], we envisaged to investigate the sequential annulation/hydroxyfluorination
reaction of propargylic carbamates/ureas (Scheme 1).
Scheme 1. Annulation/hydroxyfluorination of propargylic carbamates/ureas
Cycloisomerization reactions of these derivatives represent a viable alternative to the synthesis of products of
great interest in both the pharmaceutical [61,62] and agricultural [63] industries because of their significant
biological activities as inhibitors, sigma receptors, and antibiotics [64-69]. In fact, the introduction of the
fluoromethyl group (CH2F) is of pivotal importance in many biologically active compounds and has become a
powerful tool with regard to isostere-based drug design [70-71]. However, methods for the synthesis of

monofluoromethyl substituted molecules are quite limited [72,73], and to the best of our knowledge sequential
cycloisomerization/hydroxyfluorination reaction of propargylic carbamates/ureas is unprecedented. On the
basis of these evidences, we have investigated the synthesis of fluorometyl-hydroxy-
oxazolidinone/imidazolinone derivatives.
2. Results and discussion
Firstly, we explored the effectiveness of the NaHCO3-promoted and silver-catalyzed sequential
cyclization/hydroxyfluorination of the readily available propargylic tosylcarbamates
catalysts have been reported to effectively activate the carbon-carbon triple bond [75] by acting as a
-Lewis acid and to be crucial for the fluorination process [76-80]. Moreover, very recently a silver-
2 [74]. Silver

catalyzed hydroxyfluorination of styrenes with Selectfluor and H2O afforded vicinal fluorohydrins with
exclusive anti-Markovnikov-type regioselectivity [76]. The reaction of the spiro 1-
ethynylcyclohexyltosilcarbamate 2a with an excess of Selectfluor (2 equiv.) in the presence of a
stoichiometric amount of NaHCO3 in a mixture of CH2CN/H2O (20:1) at 60 °C achieved the isolation
of the desired 4a in 57% yield (Table 1, entry 1), unsurprisingly along with 14% of the
cycloisomerization product 4-methylene-3-tosyl-1-oxa-3-azaspiro[4,5]decan-2-one 3a as a side-
product. In fact, studies on the base promoted cyclization of O-propargylic carbamates
2 to give
enamine type derivatives were previously reported [81-83] as well as the hydroxyfluorination of the
3
2-methylene-1-tosylpyrrolidine derivatives under metal free conditions [57]. The fluoro hemiaminal
type compound 4a was isolated in higher yield in the presence of a catalytic amount of AgNO3 (0.1
equiv.) both performing the reaction at 60 °C or at room temperature for a more prolonged time (Table
1, entries 2, 3). By contrast with previously reported results AuCl resulted a less efficient catalyst (Table
1, entries 4, 5) [84,85]. However, the reaction took also place to give 4a in high yield in the absence
of NaHCO3 (Table 1, entry 6). Conversely, the fluorination reaction failed to occur, without the base,
when the catalyst was NaAuCl4·2H2O (5 mol%) and the reaction was carried out at room temperature
(Table 1, entry 7). In this latter case only a partial conversion of 2a (recovered in 36 % yield) to 3a was
observed. The starting tosylcarbamate 2a was recovered under base and metal free conditions
allowing to rule out the possibility of formation of product 4a by a direct electrophilic fluorination of the
starting carbamate 2a [86-89].

Table 1. Optimization of the sequential annulation/hydroxyfluorination of the 1-ethylcyclohexyl tosylcarbamate
2a
Entry
Base
Catalyst
Temperature (°C)
4a
time(h)
60/6
60/2
rt/24
60/2
rt/24
60/6
rt/24
60/6
% yield [a]
57 (14) [b]
87
1
2
3
4
5
6
7
8
NaHCO3
/
AgNO3
AgNO3
AuCl
NaHCO3
NaHCO3
94 (4) [b]
60
NaHCO3
NaHCO3
AuCl
60
/
/
/
AgNO3
NaAuCl4·2H2O
/
82 (4) [b]
- (38) [b]
/
[a] Isolated yields; [b] Figures in bracket refer to the isolated yield of 3a.
The requirement to combine NaHCO3 with the silver catalyst was essential in dependence on the
features of the starting tosylcarbamate
propargylic position of the carbamates
2
. Indeed, by investigating the effect of substituents at the
2
(Table 2), we found that the hydrolysis of 2b and 2c to give
tosylamide was predominant over the sequential cyclyzation/hydroxyfluorination in the absence of the
silver catalyst (4b was recovered only in low yield and 4c found only in traces, Table 2, entry 1, 2),
whereas 4b-c were isolated in good yields when 2b-c where reacted with Selectfluor in the presence
of both NaHCO3 and AgNO3 at 60 °C for 2h or at room temperature for 24h (Table 2, entries 3-5). The
prevalence of the hydrolysis of 2c was also observed by omitting NaHCO3 (Table 2, entry 6).
Table 2. Optimization of the sequential annulation/hydroxyfluorination.

Entry tosylcabamate Base [a] Catalyst [b] Temperature (°C)
time(h)
4
% yield [c]
29 (40) [d]
- (56) [d,e]
81
1
2
3
4
5
6
2b
2c
2b
2c
2c
2c
NaHCO3
NaHCO3
NaHCO3
NaHCO3
NaHCO3
/
/
60/7
60/24
60/2
/
AgNO3
AgNO3
AgNO3
AgNO3
60/2
74
rt/24
60/21
83
33 (56) [d]
[a] 1.0 equivalent, if present; [b] 0.1 equivalent, if present; [c] Isolated yields; [d] Figures in bracket refer to
the isolated yield of TsNH2; [e] 2c was recovered in 23% yield.
Secondly, the scope of the silver-catalyzed reaction of a variety of tosyl propargylic carbamates was
explored (Scheme 2).
Scheme 2. Substrate scope of the sequential silver-catalyzed annulation/hydroxyfluorination of propargylic
tosyl carbamates 2.

Notably, the Ag-catalyzed cyclization of carbamates
2 showed very high regio- and chemoselectivity
leading only to five-membered cyclic products derived from N-cyclization. In fact, in no case the silver-
catalyzed intramolecular O- 5-exo-dig annulation was observed [90]. The exclusive formation of the
Markovnikov-type hydroxyfluorination products
4 rules out their formation by means of silver-catalyzed
radical hydroxyfluorination process [76]. The N-tosyl 4-fluoromethyl-4-hydroxy-oxazolidinones
isolated usually in god to high yields. The tosylcarbamates bearing a monosubstituent (R1 =
substituent, R2 = H) or different substituent (R1 R2) at the propargylic position, gave the corresponding
4 were

fluoro derivatives as diasteromeric mixtures. The diastereomeric composition, for all fluorinated
compounds, was determined by integration of 19F NMR signals. Moreover, to shed a light on the
relative configuration of the diastereomers, we prepared the (S)-but-3-yn-2-yl tosylcarbamate (S)-2d
from the commercial available (S)-(-)-3-butyn-2-ol (Scheme 3). In consideration that the subsequent
reaction leading to the corresponding oxazolidinone should leave the stereocenter at carbon 5
unchanged, we take advantage of the NOESY experiment to easily differentiate between the two
diastereoisomers. In fact (4S,5S)-4d should show a strong NOE cross peak between the proton bound
at carbon 5 and the methylene CH2F, whereas the (4R,5S)-4d should show the opposite pattern with
a strong NOE interaction between the methyl at carbon 5 and the methylene CH2F. Data from NOESY
showed that the major isomer was (4S,5S)-4d and the minor one was (4R,5S)-4d (see Supporting
Information).
Scheme
3.
Sterochemical
outcome
of
the
sequential
silver-catalyzed
catalyzed
annulation/hydroxyfluorination of (S)-but-3-yn-2-yl tosylcarbamate 2d
.
Surprisingly, although the steroidal sterically bulky chiral counterpart in 2h was a good reaction
component, delivering the product as a single diastereoisomer (> 99:1 dr), equilibrium of the
hemiaminal type derivative 4h with the -fluoroketone 5h was observed (4h:5h = 5:95; 61% overall
yield) (Scheme 4).

Scheme 4. 4-Fluorometyl-4-hydroxy-oxazolidinone 4h vs. -fluoroketone 5h.
The formation of the
doublet at ca. 200 ppm with 2J coupling F-C of ca. 15 Hz (for 5h 203.4 ppm and 2JF-C = 14.8 Hz).
Moreover, nearly all 13C NMR signals are different for 4h and 5h
-fluoroketone is clearly shown by the appearance of a characteristic ketone
.
When the procedure was extended to the benzoylcarbamates 6a, the formation of the 4-fluoromethyl-4-
hydroxy-oxazolidinone 8a was accomplished in satisfactory yield. A better result was observed by combining
the silver catalyzed annulation with the hydroxyfluorination step in the same reaction flask (Scheme 5).
Scheme 5. Domino vs. combined silver-catalyzed annulation/hydroxyfluorination of the benzoyl
carbamate 6a
.
Usually the combined procedure allowed the isolation of the 3-benzoyl-4-(fluoromethyl)-4-hydroxy-
oxazolidin-2-ones in higher yield than the domino process. The reaction conditions resulted
8

compatible with a number of functional groups including alkyl, aryl, conjugated ketone, chloro and
bromo substituents (Scheme 6).
Scheme 6. Combined silver-catalyzed annulation/hydroxyfluorination of the benzoyl carbamates 6.
The reaction of annulation/hydroxyfluorination was substantially insensitive to change of substrate, in
fact yields and diastereomeric ratio were comparable. Monosubstituted propargylic

benzoylcarbamates 6d-j delivered the corresponding diastereo enriched products 8d-j in 82-91 %
yields with up to 90:10 dr ratio. Even if the steroidal derivative 8k was isolated as single diastereomer,
the

-fluoroketone 9k resulted the major component of the products mixture (8k
/9k = 5:95; 66% overall
yield). As well as for the tosyl derivative 4h, the formation of

-fluoroketone 9k involving an easy ring
opening of the hemiaminal type steroidal scaffold was revealed by the appearance of the characteristic
2
ketone doublet at 203.6 ppm with JF-C = 15.1 Hz. Interestingly, the hydroxyfluorination of terminal C-
C double bond tolerates the presence of an internal one. Then, the (E)-3-benzoyl-

2-azanyl)-4-
2-azanyl)-
methylene-5-(pent-1-en-1-yl)oxazolidin-2-one 7l led only to the formation of (E)-3-benzoyl-

4-(fluoromethy)-4-hydroxy-5-(pent-1-en-yl)oxazolidin-2-one 8l in almost quantitative yield (Scheme 7).
In this latter case, it was remarkable the advantage of the combined silver-free one-flask procedure
that allowed the chemoselective formation of 8l from 6l in prolonged reaction (Scheme 7, a). The
competitive 5-exo-trig annulation of 6l giving the trans-3-benzoyl-4-propyl-5-prop-2-yn-1-yl-1,3-
oxazolidin-2-one 10 was promoted by silver catalysis (Scheme 7, b) and can be avoided in the absence
of catalyst (Scheme 7, a).
Scheme 7. Silver catalyzed domino annulation/hydroxyfluorination and combined base promoted
annulation/hydroxyfluorination of the benzoyl carbamate 6l.
Although the microwave assisted formation of
-fluorohydrins from internal alkenes with Selectfluor
has been reported [91], the use of carbamates with a tethered internal alkyne which can easily
cycloisomerize to 4-arylidene/alkylideneoxazolidin-2-ones resulted unsuitable substrates for the

present process because of the lack of regio- and stereoselectivity of hydoxyfluorination step. Indeed,
while we isolated in good yield the (E)-3-tosyl-4-(3-trifluoromethyl)benzylidene)-1-oxa-3-
azaspiro[4.5]decan-2-one 12, in the following fluorination step only partial conversion (35 %) of 12 into
all the hydroxyfluoro stereoisomers 13 occurred (Scheme 8). Even worse a complex mixture of
fluoroderivatives was observed when the (E)-4-ethylidene-3-tosyloxazolidin-2-one 14 underwent
fluorination with Selectfluor under our reaction conditions (Scheme 8).
Scheme 8. Unselective hydroxyfluorination reactions.
Moreover, we tried the synthesis of a six-membered cyclic 4-(fluoromethyl)-4-hydroxy-3-tosyl-1,3-
oxazin-2-one 17 (Scheme 9). The 6-endo-dig cyclization of the but-3-yn-1-yl tosylcarbamate 15 to
the intermediate tosylenamide 16 resulted more difficult compared to 5-exo-dig process. However,
we failed to isolate compound 17 because of its fast interconversion into the -fluoroketone 18. As
seen for the synthesis of 8l, also 18 was obtained in higher yield, under silver free conditions, from
the cyclic enamide derivative 16 (Scheme 9, b).

Scheme 9. Hydroxyfluorination reaction of the but-3-yn-1-yl tosylcarbamate 15 and the 4-methylene-3-tosyl-
1,3-oxazinan-2-one 16.
Analogously the application of the procedure to the tosylurea derivative 19 showed that its cyclization
afford the imidazolidinone 20 as major product which in turn underwent hydroxyfluorination to give the
corresponding 5-(fluoromethyl)-5-hydroxy-1-tosylimidazolin-2-one 21 together with the N-((3-fluoro-2-
oxopropyl)carbamoyl)-4-methylbenzenesulfonamide 22 in 80 % overall yield (Scheme 10).
Scheme 10. Hydroxyfluorination of 5-methylene-1-tosylimidazolidin-2-one 20
.
Finally, the target 4-fluoromethyl-4-hydroxy-oxazolidinones
propargylic alcohols in a one-flask process (Scheme 11).
4 and 8 could be directly obtained from

Scheme 11. One flask synthesis of 4-fluoromethyl-4-hydroxy-oxazolidinones 4 and 8 from propargylic
alcohols.
3. Conclusions
In conclusion, the aminocylization/hydroxyfluorination of propargylic carbamates can allow an efficient
approach to the synthesis of the corresponding 4-fluoromethyl-4-hydroxy-oxazolidinones under mild
conditions with tolerance for a variety of functional groups. These Markovnikov-type derivatives can
be also obtained directly by reacting propargylic alcohols with isocyanates in the same flask. The
effectiveness
of
the
base
promoted
and
silver-catalyzed
sequential
aminocyclization/hydroxyfluorination of the readily available propargylic tosyl- and benzoylcarbamates
was thoroughly investigated. Propargylic tosyl- and benzoylcarbamates bearing different substituents
at the propargylic position gave the corresponding diastereomeric enriched fluorohydroxy-
oxazolidinones. Chiral steroidal propargylic carbamates led to the formation of the corresponding
flurohydroxyoxazolidinone derivative as a single diastereomer which was prone to interconvert into the

-fluoroketone derivative by a ring opening reaction.
4. Experimental section
4.1. Materials and methods
All reactions were carried out with magnetic stirring and were monitored by TLC on silica gel 60Å
(Fluorochem). IR spectra were recorded in KBr pellets or neat in NaCl on a Perkin-Elmer Spectrum
1
Two FT-IR spectrometer. H NMR spectra were recorded at 400 MHz on a Bruker Avance III
spectrometer. Chemical shifts (in ppm) were referenced to tetramethylsilane (δ = 0 ppm) in CDCl3 or
in Dimethyl sulfoxide-d6 (δ = 2.49 ppm) as an internal standard. 13C NMR spectra were taken on the

same machine at 100.6 MHz and were calibrated with CDCl3 (δ = 77.00 ppm) or Dimethyl sulfoxide-
d6 (δ = 30.50 ppm). 19F NMR spectra were recorded at 376 MHz and CF3COOH (δ = -76.55) was
employed as external standard for the 19F NMR measurement. Mass measurement was performed
using a MALDI-TOF spectrometer AB SCIEX TOF/TOF 5800 System. Unless otherwise stated, all
starting materials, catalysts, and solvents were commercially available and were used as purchased.
Reaction products were purified by flash chromatography on silica gel (60-200
hexane/EtOAc mixtures. All tosylcarbamates 2a [92], 2b [93], 2c [94], 2d [81], 2f [81], and 2g [95] and
benzoylcarbamates 6a [96], 6c [81], except 2e 6b 6d-l and 11, were previously described and
m) by elution with n-
,
,
prepared according to the literature. Compounds 3a [96], 15 [97], 16 [98], 19 [99] and 20 [99] are
known products and were identified by comparison of the reported physical and spectral data.
4.2. Synthesis of starting materials
4.2.1 General procedure for preparation of Tosylcarbamates (2)
To a dry 50 mL 1-necked round-bottomed flask containing the propargylic alcohol (2 mmol) dissolved in 5 mL
of THF was added TsNCO (2.2 mmol) dropwise via syringe at room temperature. After complete addition, the
reaction was allowed to stir at 60 °C for 2.0 hour. The solvent was then stripped off and the crude was purified
by flash chromatography to give the desired tosylcarbamate 2.
(8R,9S,10R,13S,14S,17R)-17-ethynyl-10,13-dimethyl-3-oxo-2,3,6,7,8,9,10,11,12,13,14,15,16,17-
tetradecahydro-1H-cyclopenta[a]phenanthren-17-yl tosylcarbamate 2h. White solid (95% yield, 0.968 g)
after purification by flash chromatography (n-Hexane/EtOAc: 75/25). IR (KBr): 3271, 2116, 1753, 1659, 1352,
667 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.93-7.91 (m, 2H, Tos), 7.34.7.32 (m, 2H, Tos), 5.74 (s, 1H, Csp2
-
H), 2.68-2.61 (m, 1H), 2.56 (s, 1H, Csp-H), 2.48-2.26 (m, 4H), 2.44 (s, 3H, CH3, Tos), 2.11-2.00 (m, 2H), 1.84
-1.31 (m, 10H), 1.19 (s, 3H, Me), 1.09-0.90 (m, 3H), 0.84 (s, 3H, Me) ppm; 13C NMR (100.6 MHz, CDCl3): δ =
199.6 (C=O), 170.9 (Cq), 148.9 (C=O), 144.8 (Cq), 135.8 (Cq), 129.5 (2CH), 128.0 (2CH), 123.9 (CH), 86.8
(Cq), 81.7 (Cspq), 76.3 (Csp-H), 53.1 (CH), 48.3 (CH), 47.6 (Cq), 38.5 (Cq), 37.1 (CH2), 35.8 (CH), 35.6 (CH2),
33.8 (CH2), 32.7 (CH2), 32.6 (CH2), 31.3 (CH2), 23.3 (CH2), 21.6 (CH2), 20.5 (Me, Tos), 17.3 (Me), 13.2 (Me)
ppm; HRMS m/z (ESI) positive ion, calculated for C29H36NO5S: [M+H]+ 510.2314, Found: 510.2310.

4.3. Typical procedure for the sequential silver-catalyzed annulation / hydoxyfluronination of
tosylcarbamates ( ): synthesis of 4-(fluoromethyl)-4-hydroxy-3-tosyl-1-oxa-3-azaspiro[4.5]decan-2-
one 4a
2
.
To a solution of 1-ethynylcyclohexyl tosylcarbamate 2a (130 mg, 0.40 mmol, 1 equiv.) in MeCN/H2O
(20:1) (2.10 mL), were added NaHCO3 (35 mg, 0.40 mmol, 1 equiv.), AgNO3 (7 mg, 0.1 equiv.) and
Selectfluor (286 mg, 0.80 mmol, 2 equiv.). After complete addition, the reaction was allowed to stir at
60 °C for 2 hours and monitored by TLC. Upon completion, the solvent was then stripped off and the
crude was purified by flash chromatography (n-Hexane/EtOAc: 80/20) to give 4-(fluoromethyl)-4-
hydroxy-3-tosyl-1-oxa-3-azaspiro[4.5]decan-2-one 4a (124 mg, 87% yield). White solid IR (KBr): 3469,
1781, 1750, 1365, 1172, 663 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.99-7.96 (m, 2H, Tos), 7.35-7.33
(m, 2H, Tos), 4.85 (dd, JH-F =46.3 Hz, JH-H =0.5 Hz, 2H, CH2F), 4.30 (br, 1H, OH), 2.44 (s, 3H, CH3,
Tos), 1.97-1.15 (m, 10H) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 150.2 (C=O), 145.9 (Cq, Tos), 134.5
(Cq, Tos), 129.7 (2CH, Tos), 129.0 (2CH, Tos), 92.3 (d, J= 21.5 Hz, Cq), 87.0 (d, J= 1.1 Hz, Cq), 81.8
(d, J= 180.7 Hz, CH2F), 30.5 (d, J= 3.9 Hz, CH2), 30.4 (CH2), 24.6 (CH2), 21.8 (CH3, Tos), 21.7 (CH2),
21.4 (CH2) ppm; 19F NMR (376.4 MHz, CDCl3): δ = -222.0 (t, J=46.3 Hz, 1F) ppm; HRMS m/z (ESI)
positive ion, calculated for C16H21FNO5S: [M+H]+ 358.1124, Found: 358.1122.
5-Ethyl-4-(fluromethyl)-4-hydroxy-5-methyl-3-tosyloxazolidin-2-one 4b. Yellow solid (110 mg,
81% yield) after purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3407, 1768,
1371, 1284, 775 cm-1; 1H NMR (400 MHz, CDCl3): δ =7.99-7.97 (m, 2H, Tos, major+minor), 7.36-7.34
(m, 2H, Tos, major+minor), 4.87 (dd, JH-F = 46.1 Hz, JH-H = 10.6 Hz, 1H, CH2F, major), 4.86 (d, JH-F
=
46.4 Hz, 2H, CH2F, minor), 4.83 (dd, JH-F = 46.6 Hz, JH-H = 10.6 Hz, 1H, CH2F, major), 4.32 (br, 1H,
OH, minor), 4.27 (br, 1H, OH, major), 2.44 (s, 5.5H, Ts-CH3, Tos, major+minor), 1.95-1.68 (m, 2H,
CH2, major+minor), 1.47 (d, JH-F = 1.9 Hz, 3H, CH3, major), 1.37 (s, 3H, CH3, minor), 1.02 (t, J =7.4,
3H, CH2CH3, minor), 0.95 (t, J =7.5, 3H, CH2CH3, major) ppm; 13C NMR (100.6 MHz, CDCl3): δ =
150.31 (C=O, major), 150.27 (C=O, minor), 145.94 (Cq, Tos, major), 145.92 (Cq, Tos, minor), 134.58
(Cq, Tos, minor), 134.55 (Cq, Tos, major), 129.68 (2CH, Tos, minor), 129.67 (2CH, Tos, major),129.01
(2CH, Tos, major), 128.97 (2CH, Tos, minor), 92.6 (d, J= 21.6 Hz, Cq, minor), 92.4 (d, J= 21.4 Hz, Cq,
major), 88.4 (d, J= 1.0 Hz, Cq, minor), 87.8 (d, J= 1.1 Hz, Cq, major), 82.2 (d, J= 181.4 Hz, CH2F,
major), 81.9 (d, J= 180.4 Hz, CH2F, minor), 28.4 (CH2, major), 27.3 (d, J= 3.5 Hz, CH2, minor), 21.8
(Ts-CH3, major+minor), 19.0 (d, J= 4.2 Hz, CH3, major), 18.7 (CH3, minor), 7.9 (CH2CH3, minor), 7.8

(CH2CH3, major) ppm; 19F NMR (376.4 MHz, CDCl3): δ = -221.1 (td, J=46.3 Hz, J=1.9 Hz, 55%), -
222,0 (t, J=46.3 Hz, 45%) ppm; HRMS m/z (ESI) positive ion, calculated for C14H19FNO5S: [M+H]+
332.0968, Found: 332.0967.
4-(Fluoromethyl)-4-hydroxy-3-tosyloxazolidin-2-one 4c. Oil (115 mg, 74% yield) after purification
1
by flash chromatography (n-Hexane/EtOAc: 80/20). IR (neat): 3345, 1774, 818 cm-1; H NMR (400
MHz, CDCl3): δ = 7.98-7.95 (m, 2H, Tos), 7.38-7.35 (m, 2H, Tos), 5.05 (dd, JH-F = 46.5 Hz, JH-H = 10.0
Hz, 1H, CH2F), 4.58 (dd, JH-F = 46.2 Hz, JH-H = 10.0 Hz, 1H, CH2F), 4.55 (br, 1H, OH), 4.45 (dd, JH-H
=
9.7 Hz, JH-F = 2.1 Hz, 1H, CH2), 4.25 (dd, JH-H = 9.7 Hz, JH-F = 2.6 Hz, 1H, CH2), 2.45 (s, 3H, Tos) ppm;
13C NMR (100.6 MHz, CDCl3): δ = 151.2 (C=O), 146.2 (Cq, Tos), 134.2 (Cq, Tos), 129.7 (2CH, Tos),
128.9 (2CH, Tos), 89.2 (d, J= 22.3 Hz, Cq), 82.1 (d, J= 180.3 Hz, CH2F), 71.7 (d, J= 2.3 Hz, CH2),
21.8 (CH3, Tos) ppm 19F NMR (376.4 MHz, CDCl3): δ = -223.6 (td, J=46.3 Hz, J=2.3 Hz, 1F, CH2F)
ppm; HRMS m/z (ESI) positive ion, calculated for C11H13FNO5S: [M+H]+ 290.0498, Found: 290.0500.
4-(Fluoromethyl)-4-hydroxy-5-methyl-3-tosyloxazolidin-2-one 4d. Yellow solid (147 mg, 90% yield) after
purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3351, 1750, 1371, 1172, 670 cm-1;
1H NMR (400 MHz, CDCl3): δ = 7.98-7.95 (m, 2H, Tos, major+minor), 7.37-7.34 (m, 2H, major+minor), 5.00
(dd, JH-F = 46.5 Hz, JH-H = 10.1 Hz, 1H, CH2F, major), 4.91 (ddd, JH-F = 46.2 Hz, JH-H = 10.5 Hz, JH-H = 0.6 Hz,
1H, CH2F, minor), 4.73 (dd, JH-F = 46.2 Hz, JH-H = 10.5 Hz, 1H, CH2F, minor), 4.66 (qd, JH-H = 6.5 Hz, JH-F = 2.0
Hz, 1H, CH, major), 4.53 (dd, JH-F = 46.5 Hz, JH-H = 10.1 Hz, 1H, CH2F, major), 4.53 (qd, JH-H = 6.5 Hz, JH-F
=
1.9 Hz, 1H, CH, minor), 4.20 (br, 1H, OH, major+minor), 2.44 (s, 3H, CH3, Tos, major), 2,43 (s, 3H, CH3, Tos,
minor), 1.50 (dd, JH-H = 6.7 Hz, JH-F = 1.8 Hz, 3H, CH3, minor), 1.41 (d, JH-H = 6.5 Hz, 3H, CH3, major) ppm;
13C NMR (100.6 MHz, CDCl3): δ = 150.9 (C=O, major), 150.5 (C=O, minor), 146.1 (Cq, Tos, minor), 146.0 (Cq,
Tos, major), 134.34 (Cq, Tos, major), 134.28 (Cq, Tos, minor), 129.72 (2CH, Tos, minor), 129.70 (2CH, Tos,
major), 128.98 (2CH, Tos, minor), 128.96 (2CH, Tos, major), 91.0 (d, J= 21.7 Hz, Cq, minor), 89.8 (d, J= 21.0
Hz, Cq, major), 82.1 (d, J= 180.6 Hz, CH2F, major), 80.9 (d, J= 0.8 Hz, CH, minor), 80.6 (d, J= 181.0 Hz, CH2F,
minor), 77.2 (d, J= 2.2 Hz, CH, major), 21.76 (CH3, Tos, minor), 21.75 (CH3, Tos, major), 14.1 (d, J= 4.0 Hz,
CH3, minor), 13.5 (d, J= 0.9 Hz, CH3, major) ppm; 19F NMR (376.4 MHz, CDCl3): δ = -222.1 (td, J=46.2 Hz,
J=1.9 Hz, 19%), -223,9 (td, J=46.5 Hz, J=2.0 Hz, 81%) ppm; HRMS m/z (ESI) positive ion, calculated for
C12H15FNO5S: [M+H]+ 304.0655, Found: 304.0657.

4-(Fluoromethyl)-4-hydroxy-3-tosyl-1-oxa-3-azaspiro[4.4]nonan-2-one 4e. White solid (154 mg,
91% yield) after purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3326, 1743,
1
1172, 1346, 1172, 676 cm-1; H NMR (400 MHz, CDCl3): δ = 7.99-7.97 (m, 2H, Tos), 7.36-7.34 (m,
2H, Tos), 4.91 (dd, JH-F =46.3 Hz, JH-H =10.5 Hz, 1H, CH2F), 4.76 (dd, JH-F =46.3 Hz, JH-H =10.5 Hz,
1H, CH2F), 4.35 (br, 1H, OH), 2.45 (s, 3H, CH3), 2.19-1.72 (m, 8H) ppm; 13C NMR (100.6 MHz, CDCl3):
δ = 150.3 (C=O), 145.9 (Cq, Tos), 134.6 (Cq, Tos), 129.7 (2CH, Tos), 128.9 (2CH, Tos), 96.8 (d, J=
1.1 Hz, Cq), 91.2 (d, J= 21.5 Hz, Cq), 82.2 (d, J= 181.5 Hz, CH2F), 33.1 (CH2), 33.0 (d, J= 3.5 Hz,
CH2), 23.0 (CH2), 21.8 (CH3, Tos), 21.7 (CH2) ppm; 19F NMR (376.4 MHz, CDCl3): δ = -221.76 (t,
J=46.3 Hz, 1F) ppm; HRMS m/z (ESI) positive ion, calculated for C15H19FNO5S: [M+H]+ 344.0968,
Found: 344.0972.
4-(Fluoromethyl)-4-hydroxy-5,5-dimethyl-3-tosyloxazolidin-2-one 4f. White solid (125 mg, 84%
yield) after purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3475, 1781 1284,
1172, 670 cm-1; 1H NMR (400 MHz, CDCl3): δ = 8.00-7.96 (m, 2H, Tos), 7.37-7.33 (m, 2H, Tos), 4.87
(dd, JH-F =46.3 Hz, JH-H = 0.9 Hz, 2H, CH2F), 4.26 (br, 1H, OH), 2.44 (s, 3H, CH3, Tos ), 1.53 (d, J =
1.7 Hz, 3H, CH3), 1.43 (s, 3H, CH3) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 150.3 (C=O), 146.0 (Cq,
Tos), 134.5(Cq, Tos), 129.7 (2CH, Tos), 129.0 (2CH, Tos), 92.0 (d, J= 21.8 Hz, Cq), 86.0 (Cq), 82.2
(d, J= 180.4 Hz, CH2F), 22.8 (CH3), 22.3 (d, J= 3.8 Hz, CH3), 21.7 (CH3, Tos) ppm; 19F NMR (376.4
MHz, CDCl3): δ = -222.36 (t, J=46.1 Hz, 1F) ppm; HRMS m/z (ESI) positive ion, calculated for
C13H17FNO5S: [M+H]+ 318.0811, Found: 318.0813.
4-(Fluoromethyl)-4-hydroxy-5-phenyl-3-tosyloxazolidin-2-one 4g. Oil (105 mg, 78% yield) after purification
1
by flash chromatography (n-Hexane/EtOAc: 80/20). IR (neat): 3438, 1371, 1787, 1172, 676 cm-1; H NMR
(400 MHz, CDCl3): δ = 8.02-7.99 (m, 2H, major +minor), 7.43-7.31 (m, 7H, major+minor), 5.56 (d, J= 2.0 Hz,
1H, CH-Ph, major), 5.45 (s, 1H, CH-Ph, minor), 5.18 (dd, JH-F = 46.5 Hz, J= 10.2 Hz, 1H, CH2F, major), 4.61
(ddd, JH-F = 46.3 Hz, J= 10.2 Hz, J= 0.9 Hz, 1H, CH2F, minor), 4.57 (dd, JH-F= 46.4 Hz, J= 10.2 Hz, 1H, CH2F,
major), 4.06 (dd, JH-F= 45.7 Hz, J= 10.2 Hz, 1H, CH2F, minor), 3.74 (br, 1H, OH, major +minor), 2.46 (s, 3H,
Tos-Me, major +minor) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 151.2 (C=O), 150.5 (C=O), 146.2 (Cq), 146.0
(Cq), 134.5 (Cq), 134.3 (Cq), 131.0 (Cq), 130.5 (Cq), 130.0 (2CH), 129.7 (CH), 129.7 (2CH), 129.6 (CH), 129.2
(d, J= 0.7 Hz, 2CH), 129.1 (d, J= 0.6 Hz, 2CH), 128.8 (2CH), 128.7 (2CH), 127.5 (d, J= 0.3 Hz, 2CH), 126.4
(d, J= 1.8 Hz, 2CH), 92.1 (d, J= 21.0 Hz, Cq), 90.2 (d, J= 20.6 Hz, Cq), 85.4 (CH), 81.43 (d, J= 180.6 Hz,

CH2F), 81.40 (d, J= 2.2 Hz, CH), 80.2 (d, J= 181.0 Hz, CH2F), 22.8 (CH3) ppm; 19F NMR (376.4 MHz, CDCl3):
δ = -222.9 (t, J=45.9 Hz, 35 %), -223.4 (t, J=46.7 Hz 65 %) ppm; HRMS m/z (ESI) positive ion, calculated for
C17H17FNO5S: [M+H]+ 366.0811, Found: 366.0815.
(8R,9S,10R,13S,14S)-4’-(fluoromethyl)-4’-hydroxy-10,13-dimethyl-3’-tosyl-
1,6,7,8,9,10,11,12,13,14,15,16-dodecahydrospiro[cyclopenta[a]phenanthrene-17,5’-
oxazolidine]-2’,3(2H)-dione 4h (minor) and (8R,9S,10R,13S,14S)-17(2-fluoroacetyl)-10,13-
dimethyl-3-oxo-2,3,6,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-
cyclopenta[a]phenanthrene-17-yl tosylcarbamate 5h (major). White solid (83 mg, 61% yield) after
purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3438, 3252, 1743, 1656,
1458, 1166, 806, 670 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.92-7.90 (m, 2H, Tos, 5h), 7.72-7.70 (m,
2H, Tos, 4h), 7.55-7.53 (m, 2H, Tos, 4h), 7.37-7.35 (m, 2H, Tos, 5h), 5.76 (s, 1H, 4h), 5.74 (s, 1H,
5h), 4.76 (dd, JH-F = 46.7 Hz, JH-H = 16.6 Hz, 1H, CH2F, 4h), 4.66 (dd, JH-F = 47.2 Hz, JH-H = 15.7 Hz,
1H, CH2F, 5h), 4.47 (dd, JH-F = 46.6 Hz, JH-H = 15.7 Hz, 1H, CH2F, 5h), 2.75-2.62 (m, 1H, CH2, 4h
2.46 (s, 3H, CH3, Tos, 4h 5h), 2.42-2.26 (m, 4H, CH2, 4h 5h), 2.00-1.95 (m, 1H, CH2, 4h 5h), 1.85-
1.56 (m, 7H, CH2, 4h
+5h),
+
+
+
+
5h), 1.46-1.26 (m, 3H, CH+CH2, 4h
+5h), 1.20 (s, 3H, CH3, 4h), 1.17 (s, 3H,
CH3, 5h), 1.11-0.81 (m, 3H, CH+CH2, 4h
+
5h) 0.98 (s, 3H, CH3, 5h), 0.92 (s, 3H, CH3, 4h) ppm; 13C
NMR (100.6 MHz, CDCl3): δ = 203.4 (d, J= 14.8 Hz, C=O, 5h), 199.8 (C=O, 4h), 199.7 (C=O, 5h),
170.93 (Cq, 4h), 170.87 (Cq, 5h), 150.8 (C=O, 5h), 149.8 (Cq, 4h), 146.1 (Cq, Tos, 4h), 145.4 (Cq,
Tos, 5h), 135.5 (Cq, Tos, 5h), 132.4 (Cq, Tos, 4h), 130.9 (2CH, Tos, 4h), 129.7 (2CH, Tos, 5h), 128.8
(2CH, Tos, 4h), 128.1 (2CH, Tos, 5h), 124.01 (CH, 5h), 123.98 (CH, 4h), 97.2 (Cq, 5h), 89.3 (Cq, 4h),
84.2 (d, J= 184.6 Hz, CH2, 5h), 82.8 (d, J= 185.6 Hz, CH2, 4h), 53.1 (CH, 4h), 52.7 (CH, 5h), 48.9
(CH, 4h), 48.2 (Cq, 5h), 47.1 (CH, 5h), 46.9 (Cq, 4h), 38.6 (Cq, 4h), 38.4 (Cq, 5h), 35.7 (CH2, 4h),
35.6 (CH2, 5h), 35.5 (CH, 4h
+5h), 33.9 (CH2, 4h), 33.8 (CH2, 5h), 33.4 (CH2, 4h+5h), 33.2 (CH2, 4h),
33.1 (CH2, 5h), 32.6 (CH2, 5h), 31.4 (CH2, 4h), 31.3 (CH2, 5h), 24.3 (CH2, 5h), 23.6 (CH2, 4h), 21.8
(CH3, Tos, 4h), 21.7 (CH3, Tos, 5h), 17.4 (CH3, 4h), 17.3 (CH3, 5h), 14.8 (CH3, 5h), 14.1 (CH3, 4h
)
ppm; 19F NMR (376.4 MHz, CDCl3): δ = -221.90 (t, J=46.7 Hz, 4h, 5%), -231.72 (t, J=46.9 Hz, 5h
,
95%) ppm; HRMS m/z (ESI) positive ion, calculated for 4h C22H33FNO4: [M+H]+ 394.2394, Found:
394.2387; HRMS m/z (ESI) positive ion, calculated for 5h C29H36FKNO6S: [M+K]+ 584.1884, Found:
584.1876.

4.4. General procedure for preparation of Benzoylcarbamates (6).
To a dry 50 mL 1-necked round-bottomed flask containing the propargylic alcohol (2 mmol) dissolved
in 5 mL of DCE was added BzNCO (2.2 mmol) dropwise via syringe at room temperature. After
complete addition, the reaction was allowed to stir at room temperature for 1 hour. The solvent was
then stripped off and the crude was purified by flash chromatography to give the desired
benzoylcarbamate 6.
2-Methylbut-3-yn-2-ylbenzoylcarbamate 6b. White solid (88% yield, 0.407 g) after purification by
flash chromatography (n-Hexane/EtOAc: 75/25). IR (KBr): 3288, 3199, 2120, 1766, 1527, 1218, 696
cm-1; 1H NMR (400 MHz, CDCl3): δ = 8.36 (s, 1H, NH), 7.86-7.84 (m, 2H, Bz), 7.59-7.55 (m, 1H, Bz),
7.48-7.45 (m, 2H, Bz), 2.59 (s, 1H, Csp-H), 1.76 (s, 6H, 2CH3) ppm; 13C NMR (100.6 MHz, CDCl3): δ =
165.1 (C=O, Bz), 149.1 (C=O), 133.1 (Cq, Bz), 132.9 (CH), 128.8 (2CH), 127.7 (2CH), 83.8 (Cspq),
74.0 (Cq), 73.3 (Csp-H), 28.8 (2CH3) ppm; HRMS m/z (ESI) positive ion, calculated for C13H13KNO3:
[M+K]+ 270.0533, Found: 270.0528.
But-3-yn-2-ylbenzoylcarbamate 6d. White solid (95% yield, 0. 412 g) after purification by flash
chromatography (n-Hexane/EtOAc: 75/25). IR (KBr): 3270, 3188, 2129, 1775, 1678, 1519, 1209, 714
cm-1; 1H NMR (400 MHz, CDCl3): δ = 8.54 (s, 1H, NH), 7.90-7.87 (m, 2H, Bz), 7.60-7.56 (m, 1H, Bz),
7.50-7.45 (m, 2H, Bz), 5.52 (qd, J = 6.7 Hz, J = 2.2 Hz, 1H), 2.51 (d, J = 2.2 Hz, 1H, Csp-H), 1.55 (d, J
= 6.7 Hz, 3H, CH3) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 165.0 (C=O, Bz), 149.8 (C=O), 133.1 (CH),
132.8 (Cq, Bz), 128.8 (2CH), 127.8 (2CH), 81.3 (Cspq), 74.0 (Csp-H), 62.1 (CH), 21.3 (CH3) ppm; HRMS
m/z (ESI) positive ion, calculated for C12H11KNO3: [M+K]+ 256.0376, Found: 256.0380.
Pent-1-yn-3-ylbenzoylcarbamate 6e. Oil (90% yield, 0.416 g) after purification by flash
chromatography (n-Hexane/EtOAc: 75/25). IR (neat): 3270, 3226, 2120, 1757, 1687, 1527, 1209, 714
cm-1; 1H NMR (400 MHz, CDCl3): δ = 8.49 (s, 1H, NH), 7.89-7.86 (m, 2H, Bz), 7.60-7.56 (m, 1H, Bz),
7.50-7.46 (m, 2H, Bz), 5.40 (td, J = 6.5 Hz, J = 2.2 Hz, 1H), 2.51 (d, J = 2.2 Hz, 1H, Csp-H), 1.85 (m,
2H, CH2), 1.04 (d, J = 7.4 Hz, 3H, CH3) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 164.9 (C=O, Bz),
150.0 (C=O), 133.1 (CH), 132.8 (Cq, Bz), 128.8 (2CH), 127.8 (2CH), 80.2 (Cspq), 74.6 (Csp-H), 67.0
(CH), 27.9 (CH2), 9.1 (CH3) ppm; HRMS m/z (ESI) positive ion, calculated for C13H13KNO3: [M+K]+
270.0533, Found: 270.0535.

1-Phenylprop-2-yn-1-ylbenzoylcarbamate 6f. Yellow solid (83% yield, 0.463 g) after purification by flash
chromatography (n-Hexane/EtOAc: 85/15). IR (KBr): 3296, 2129, 1775, 1695, 1492, 890 cm-1; 1H NMR (400
MHz, CDCl3): δ = 8.40 (s, 1H, NH), 7.83-7.80 (m, 2H), 7.58-7.54 (m, 3H), 7.47-7.42 (m, 2H), 7.38-7.35 (m,
3H), 6.51 (d, J = 2.3 Hz, 1H), 2.72 (d, J = 2.3 Hz, 1H, Csp-H) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 164.8
(C=O, Bz), 149.7 (C=O), 135.6 (Cq), 133.1 (CH, Bz), 132.7 (Cq, Bz), 129.4 (CH), 128.81 (2CH, Bz), 128.77
(2CH), 128.0 (2CH), 127.7 (2CH, Bz), 79.4 (Cspq), 76.6 (Csp-H), 67.2 (CH) ppm; HRMS m/z (ESI) positive ion,
calculated for C17H13KNO3: [M+K]+ 318.0533, Found: 318.0531.
1-(3-bromophenyl)prop-2-yn-ylbenzoylcarbamate 6g. White solid (83% yield, 0.296 g) after purification by
flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3327, 3220, 2111, 1776, 1753, 1524, 1189, 691
cm-1; 1H NMR (400 MHz, CDCl3): δ = 8.40 (s, 1H, NH), 7.85-7.82 (m, 2H), 7.71 (t, J = 1.8 Hz, 1H), 7.57 (tt, J =
7.4 Hz, J = 1.3 Hz, 1H), 7.51-7.44 (m, 4H), 7.24 (t, J = 7.9 Hz, 1H), 6.47 (d, J = 2.3 Hz, 1H), 2.74 (d, J = 2.3
Hz, 1H, Csp-H) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 164.7 (C=O, Bz), 149.5 (C=O), 137.8 (Cq), 133.2 (CH,
Bz), 132.6 (Cq, Bz), 132.5 (CH), 130.9 (CH), 130.3 (CH), 128.9 (2CH, Bz), 127.7 (2CH, Bz), 126.6 (CH), 122.7
(CBr), 78.8 (Cspq), 77.1 (Csp-H), 66.3 (CH) ppm; HRMS m/z (ESI) positive ion, calculated for C17H12BrKNO3:
[M+K]+ 395.9638, Found: 395.9636.
1-(4-Chlorophenyl)prop-2-yn-ylbenzoylcarbamate 6h. Yellow solid (82% yield, 0.278 g) after
purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3305, 3243, 2120, 1750,
1492, 1200, 687 cm-1; 1H NMR (400 MHz, CDCl3): δ = 8.47 (s, 1H, NH), 7.85-7.82 (m, 2H), 7.59-7.55
(m, 1H), 7.50-7.43 (m, 4H), 7.34-7.31 (m, 2H), 6.48 (d, J = 2.3 Hz, 1H), 2.73 (d, J = 2.3 Hz, 1H, Csp-
H) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 164.8 (C=O, Bz), 149.7 (C=O), 135.5 (Cq), 134.2 (CCl),
133.2 (CH, Bz), 132.6 (Cq, Bz), 129.4 (2CH), 129.0 (2CH), 128.9 (2CH, Bz), 127.8 (2CH, Bz), 79.0
(Cspq), 76.9 (Csp-H), 66.4 (CH) ppm; HRMS m/z (ESI) positive ion, calculated for C17H12ClKNO3:
[M+K]+ 352.0143, Found: 352.0140.
1-(Naphthalen-1-yl)prop-2-yn-yl benzoylcarbamate 6i. Yellow solid (94% yield, 0.403 g) after
purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3285, 2125, 1757, 1510,
1
1189, 770 cm-1; H NMR (400 MHz, CDCl3): δ = 8.20 (br, 1H, NH), 7.90-7.88 (m, 3H), 7.77-7.75 (m,
2H), 7.60-7.40 (m, 7H), 7.18 (d, J = 2.3 Hz, 1H), 2.79 (d, J = 2.3 Hz, 1H, Csp-H) ppm; 13C NMR (100.6

MHz, CDCl3): δ = 164.7 (C=O, Bz), 149.6 (C=O), 134.0 (Cq), 133.1 (CH, Bz), 132.7 (Cq, Bz), 130.8
(Cq), 130.5 (CH), 130.4 (Cq), 128.9 (CH), 128.8 (2CH, Bz), 127.6 (2CH, Bz), 127.1 (CH), 127.0 (CH),
126.2 (CH), 125.2 (CH), 123.5 (CH), 79.3 (Cspq), 77.2 (Csp-H), 65.6 (CH) ppm; HRMS m/z (ESI)
positive ion, calculated for C21H15KNO3: [M+K]+ 368.0689, Found: 368.0686.
3-Methylpent-1-yn benzoylcarbamate 6j. White solid (86% yield, 0.422 g) after purification by flash
chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3296, 3196, 2111, 1766, 1536, 1230, 775 cm-1; 1H NMR
(400 MHz, CDCl3): δ = 8.31 (br, 1H, NH), 7.86-7.83 (m, 2H), 7.59-7.55 (m, 1H), 7.49-7.45 (m, 2H), 2.60 (s, 1H,
Csp-H), 2.16-2.03 (m, 1H, CH2), 1.97-1.87 (m, 1H, CH2), 1.77 (s, 3H, Me), 1.08 (t, J = 7.4 Hz, 3H, Me) ppm;
13C NMR (100.6 MHz, CDCl3): δ = 165.0 (C=O, Bz), 149.2 (C=O), 133.1 (Cq), 132.9 (CH), 128.8 (2CH, Bz),
127.7 (2CH, Bz), 82.8 (Cspq), 78.0 (Cq), 74.2 (Csp-H), 34.4 (CH2CH3), 26.0 (CH2CH3), 8.5 (CH3) ppm; HRMS
m/z (ESI) positive ion, calculated for C14H15KNO3: [M+K]+ 284.0689, Found: 284.0691.
(8R,9S,10R,13S,14S,17R)-17-ethynyl-10,13-dimethyl-3-oxo-2,3,6,7,8,9,10,11,12,13,14,15,16,17-
tetradecahydro-1H-cyclopenta[a]phenanthren-17-yl benzoylcarbamate 6k. White solid (52%
yield, 0.477 g) after purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3283,
3261, 2111, 1793, 1660, 1492, 1182, 705 cm-1; 1H NMR (400 MHz, CDCl3): δ = 8.45 (s, 1H, NH), 7.87-
7.85 (m, 2H, Bz), 7.60-7.56 (m, 1H, Bz), 7.50-7.46 (m, 2H, Bz), 5.73 (s, 1H, Csp2-H), 2.84-2.76 (m, 1H),
2.68 (s, 1H, Csp-H), 2.47-2.17 (m, 5H), 2.08-2.02 (m, 1H), 1.89-1.36 (m, 10H), 1.20 (s, 3H, Me), 1.16-
0.90 (m, 2H), 1.00 (s, 3H, Me) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 199.5 (C=O), 170.9 (Cq), 164.9
(C=O), 150.2 (C=O), 133.1 (Cq), 132.9 (CH), 128.8 (2CH), 127.8 (2CH), 123.9 (CH), 86.4 (Cq), 82.3
(Cq), 76.2 (Csp-H), 53.2 (CH), 48.4 (CH), 47.7 (Cq), 38.6 (Cq), 37.3 (CH2), 35.9 (CH), 35.6 (CH2), 33.9
(CH2), 32.8 (CH2), 32.7 (CH2), 31.5 (CH2), 23.5 (CH2), 20.6 (CH2), 17.4 (Me), 13.5 (Me) ppm; HRMS
m/z (ESI) positive ion, calculated for C29H33KNO4: [M+K]+ 498.2047, Found: 498.2044.
(E)-Oct-4-en-1-yn-3-ylbenzoylcarbamate 6l. Yellow solid (76% yield, 0.412 g) after purification by
flash chromatography (n-Hexane/EtOAc: 95/5). IR (KBr): 3294, 3243, 2120, 1771, 1687, 1534, 1194,
1
709 cm-1; H NMR (400 MHz, CDCl3): δ = 8.35 (br, 1H, NH), 7.87-7.84 (m, 2H), 7.60-7.56 (m, 1H),
7.49-7.45 (m, 2H), 6.12-6.04 (m, 1H), 5.93-5.90 (m, 1H), 5.59 (ddt J = 15.3 Hz, J = 6.7 Hz, J = 1.5 Hz,
1H), 2.62 (d, J = 2.2 Hz, 1H, Csp-H), 2.05 (q, J = 6.7 Hz, 2H), 1.41 (td, J = 14.8 Hz, J = 7.4 Hz, 2H),
0.91 (t, J = 7.4 Hz, 3H, Me) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 164.8 (C=O, Bz), 149.7 (C=O),

138.1 (CH), 133.1 (CH, Bz), 132.9 (Cq, Bz), 128.9 (2CH, Bz), 127.7 (2CH, Bz), 123.9 (CH), 79.1 (Cspq),
75.8 (Csp-H), 66.1 (CH), 34.0 (CH2), 21.8 (CH2), 13.6 (Me) ppm; HRMS m/z (ESI) positive ion,
calculated for C16H17KNO3: [M+K]+ 310.0845, Found: 310.0850.
(E)-3-(benzoyl-2-azanyl)-4-methylene-5-(pent-1-en-1-yl)oxazolidin-2-one 7l. Yellow solid (45% yield,
0.048 g) after purification by flash chromatography (n-Hexane/EtOAc: 95/5). IR (KBr): 1780, 1706, 1347, 1194,
760 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.69-7.66 (m, 2H), 7.59-7.54 (m, 1H), 7.46-7.41 (m, 2H), 6.02 (dtd,
J = 15.1 Hz, J = 6.8 Hz, J = 0.6 Hz, 1H), 5.64 (dd, J = 2.4 Hz, J = 2.3 Hz, 1H), 5.54 (ddt, J = 15.1 Hz, J = 8.1
Hz, J = 1.5 Hz, 1H), 5.41 (dt, J = 8.1 Hz, J = 2.2 Hz, 1H), 4.62 (t, J = 2.2 Hz, 1H), 2.13 (qt, J = 7.4 Hz, J = 1.4
Hz, 2H), 1.48 (sextet, J = 7.4 Hz, 2H), 0.94 (t, J = 7.4 Hz, 3H, Me) ppm; 13C NMR (100.6 MHz, CDCl3): δ =
169.0 (C=O, Bz), 152.8 (C=O), 140.1 (Cq), 139.9 (CH), 133.4 (Cq, Bz), 132.9 (CH, Bz), 129.1 (2CH), 128.2
(2CH), 124.7 (CH), 94.0 (Csp2H2), 79.8 (CH), 34.1 (CH2), 21.8 (CH2), 13.6 (Me) ppm; HRMS m/z (ESI) positive
ion, calculated for C16H17KNO3: [M+K]+ 310.0845, Found: 310.0845.
4.5. Typical procedure for the combined silver-catalyzed annulation /hydoxyfluronination of
benzoylcarbamates (6): synthesis of 3-Bezoyl-4-(fluoromethyl)-4-hydroxy-1-oxa-3-azaspiro[4.5]decan-2-one
8a.
To a solution of 1-ethynylcyclohexyl benzoylcarbamate 6a (104 mg, 0.38 mmol, 1 equiv.) in MeCN/H2O (20:1)
(2.10 mL), ere added NaHCO3 (32 mg, 0.38 mmol, 1 equiv.) and AgNO3 (6 mg, 0.038 mmol, 0.1 equiv.). After
complete addition, the reaction was allowed to stir at 60 °C and monitored by TLC. Then, Selectfluor (269 mg,
0.76 mmol, 2 equiv.) was added to the reaction mixture which was allowed to stir at 60 °C. Upon completion,
the solvent was then stripped off and the crude was purified by flash chromatography (n-Hexane/EtOAc: 80/10)
to give the 3-bezoyl-4-(fluoromethyl)-4-hydroxy-1-oxa-3-azaspiro[4.5]decan-2-one 8a (108 mg, 92% yield).
White solid. IR (KBr): 3500, 1787, 1681, 1265, 694 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.71-7.69 (m, 2H,
Bz), 7.62-7.57 (m, 1H, Bz), 7.47-7.43 (m, 2H, Bz), 4.85 (dd, JH-F = 46.4 Hz, JH-H = 10.5 Hz, 1H, CH2F), 4.71
(dd, JH-F = 46.4 Hz, JH-H = 10.5 Hz, 1H, CH2F), 4.47 (br, 1H, OH), 2.23-2.08 (m, 2H, CH2), 1.78-1.56 (m, 8H,
CH2) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 173.1 (C=O, Bz), 151.7 (C=O), 133.6 (CH), 132.6 (Cq), 129.5
(2CH), 128.2 (2CH), 90.2 (d, J= 19.0 Hz, Cq), 86.3 (d, J= 1.3 Hz, Cq), 79.9 (d, J= 182.9 Hz, CH2F), 31.3 (d,
J= 4.7 Hz, CH2), 29.2 (CH2), 24.8 (CH2), 21.6 (d, J= 1.0 Hz, CH2), 21.5 (CH2) ppm; 19F NMR (376.4 MHz,
CDCl3): δ = -221.9 (t, J=46.4 Hz) ppm; HRMS m/z (ESI) positive ion, calculated for C16H18FKNO4: [M+K]+
346.0857, Found: 346.0856.

3-Benzoyl-4-(fluoromethyl)-4-hydroxy-5,5-dimethyloxazolidin-2-one 8b. White solid (105 mg,
91% yield) after purification by flash chromatography (n-Hexane/EtOAc: 85/15). IR (KBr): 3500, 1775,
1695, 1306, 714 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.72-7.69 (m, 2H), 7.62-7.55 (m, 1H), 7.47-7.43
(m, 2H), 4.87 (dd, JH-F = 46.3 Hz, JH-H = 10.5 Hz, 1H, CH2F), 4.70 (dd, JH-F = 46.3 Hz, JH-H = 10.5 Hz,
1H, CH2F), 4.56 (br, 1H, OH), 1.63 (d, JH-F = 2.9 Hz, 3H, CH3), 1.56 (s, 3H, CH3) ppm; 13C NMR (100.6
MHz, CDCl3): δ = 172.9 (C=O, Bz), 151.7 (C=O), 133.6 (CH), 132.5 (Cq), 129.5 (2CH), 128.2 (2CH),
90.0 (d, J= 19.3 Hz, Cq), 85. 2 (d, J= 1.0 Hz, Cq), 80.2 (d, J= 182.6 Hz, CH2F), 23.1 (d, J= 5.0 Hz,
CH3), 21.5 (CH3) ppm; 19F NMR (376.4 MHz, CDCl3): δ = -222.2 (tq, J=46.3 Hz, J=2.9 Hz) ppm; HRMS
m/z (ESI) positive ion, calculated for C13H14FNO4: [M+H]+ 268.0985, Found: 268.0989.
3-Benzoyl-4-(fluoromethyl)-4-hydroxyoxazolidin-2-one 8c. White solid (95mg, 90% yield) after
purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3500, 1775, 1695, 1306, 714
1
cm-1; H NMR (400 MHz, CDCl3): δ = 7.73-7.70 (m, 2H), 7.64-7.60 (m, 1H), 7.50-7.45 (m, 2H), 4.91
(dd, JH-F = 46.5 Hz, JH-H = 10.2 Hz, 1H, CH2F), 4.71 (br, 1H, OH), 4.56 (dd, JH-H = 9.6 Hz, JH-F = 2.8
Hz, 1H, CH2), 4.44 (dd, JH-F = 46.5 Hz, JH-H = 10.2 Hz, 1H, CH2F), 4.35 (dd, JH-H = 9.6 Hz, JH-F = 2.8
Hz, 1H, CH2) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 172.7 (C=O, Bz), 152.2 (C=O), 133.8 (CH),
132.1 (Cq), 129.7 (2CH), 128.2 (2CH), 88.2 (d, J= 20.1 Hz, Cq), 79.2 (d, J= 181.8 Hz, CH2F), 70.2
(CH2) ppm; 19F NMR (376.4 MHz, CDCl3): δ = -221.4 (tt, J=46.5 Hz, J=2.8 Hz) ppm; HRMS m/z (ESI)
positive ion, calculated for C11H11FNO4: [M+H]+ 240.0672, Found: 240.0675.
3-Benzoyl-4-(fluoromethyl)-4-hydroxy-5-methyloxazolidin-2-one 8d. White solid (110 mg, 85% yield) after
purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3429, 1784, 1678, 1262, 776 cm-1;
1H NMR (400 MHz, CDCl3): δ = 7.74-7.72 (m, 2H, major), 7.70-7.68 (m, 2H, minor), 7.64-7.58 (m, 1H,
major+minor), 7.48-7.44 (m, 2H, major+minor), 4.97 (dd, JH-F = 46.4 Hz, JH-H = 10.4 Hz, 1H, CH2F, minor), 4.85
(dd, JH-F = 47.2 Hz, JH-H = 10.3 Hz, 1H, CH2F, major), 4.69 (dd, JH-F = 46.2 Hz, JH-H = 10.5 Hz, 1H, CH2F,
minor), 4.36 (dd, JH-F = 46.1 Hz, JH-H = 10.3 Hz, 1H, CH2F, major), 4.81 (qd, JH-H = 6.6 Hz, JH-F = 2.5 Hz, 1H,
CH-Me, major+minor), 4.55 (br, 1H, OH, major+minor), 1.61 (dd, JH-H = 6.8 Hz, JH-F = 2.4 Hz, 3H, CH3, minor),
1.51 (d, JH-H = 6.6 Hz, 3H, CH3, major) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 173.2 (C=O, Bz, major), 172.8
(C=O, Bz, minor), 152.1 (C=O, major), 151.6 (C=O, minor), 133.8 (CH, Bz, major), 133.5 (CH, Bz, minor),
132.5 (Cq, Bz, minor), 132.2 (Cq, Bz, major), 129.8 (2CH, Bz, major), 129.4 (2CH, Bz, minor), 128.24 (2CH,

Bz, major), 128.16 (2CH, Bz, minor), 89.3 (d, J= 19.8 Hz, Cq, minor), 88.6 (d, J= 18.6 Hz, Cq, major), 79.2 (d,
J= 181.9 Hz, CH2F, minor), 76.6 (d, J= 182.6 Hz, CH2 F, major), 75.6 (d, J= 1.3 Hz, CH, major+minor), 14.8
(d, J= 4.8 Hz, CH3, minor), 12.3 (CH3, major) ppm; 19F NMR (376.4 MHz, CDCl3): δ = -221.9 (ddd, J=47.2 Hz,
J=46.2 Hz, J=2.4 Hz, 86%), -222.3 (td, J=46.2 Hz, J=2.4 Hz, 14%) ppm; HRMS m/z (ESI) positive ion,
calculated for C12H12FKNO4: [M+K]+ 292.0387, Found: 292.0391.
3-Benzoyl-5-ethyl-4-(fluoromethyl)-4-hydroxyoxazolidin-2-one 8e. White solid (91% yield, 0.113
g) after purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3456, 1784, 1669,
1253, 714 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.73-7.71 (m, 2H, major), 7.69-7.67 (m, 2H, minor),
7.62-7.58 (m, 1H, major+minor), 7.47-7.43 (m, 2H, major+minor), 4.91 (ddd, JH-F = 46.4 Hz, JH-H = 10.4
Hz, JH-H = 0.6 Hz, 1H, CH2F, minor), 4.85 (dd, JH-F = 47.3 Hz, JH-H = 10.3 Hz, 1H, CH2F, major), 4.67
(dd, JH-F = 46.1 Hz, JH-H = 10.4 Hz, 1H, CH2F, minor), 4.61 (br, 1H, OH, major+minor), 4.56 (ddd, JH-H
= 9.0 Hz, JH-H = 4.7 Hz, JH-F = 2.6 Hz, 1H, CH-Et, major+minor), 4.36 (dd, JH-F = 46.2 Hz, JH-H = 10.3
Hz, 1H, CH2F, major), 2.04-1.79 (m, 2H, CH2-Me, major+minor), 1.16 (td, J = 7.4 Hz, J = 0.4 Hz, 3H,
CH3, minor), 1.14 (t, J = 7.5 Hz, 3H, CH3, major) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 173.1 (C=O,
Bz, major), 172.6 (C=O, Bz, minor), 152.1 (C=O, major), 151.7 (C=O, minor), 133.8 (CH, Bz, major),
133.4 (CH, Bz, minor), 132.6 (Cq, Bz, minor), 132.3 (Cq, Bz, major), 129.7 (2CH, Bz, major), 129.3
(2CH, Bz, minor), 128.2 (2CH, Bz, major), 128.1 (2CH, Bz, minor), 89.3 (d, J= 19.9 Hz, Cq, minor),
88.7 (d, J= 18.6 Hz, Cq, major), 85.2 (d, J= 1.3 Hz, CH-Et, minor), 80.6 (d, J= 1.2 Hz, CH-Et, major),
79.1 (d, J= 181.5 Hz, CH2F, minor), 79.0 (d, J= 181.5 Hz, CH2F, major), 22.4 (d, J= 4.3 Hz, CH2Me,
minor), 20.7 (CH2Me, major), 10.3 (CH3, minor), 10.0 (CH3, major) ppm; 19F NMR (376.4 MHz, CDCl3):
δ = -221.6 (td, J=46.7 Hz, J=2.4 Hz, 90%), -222.0 (t, J=46.4 Hz, 10%) ppm; HRMS m/z (ESI) positive
ion, calculated for C13H14FKNO4: [M+K]+ 306.0544, Found: 306.0545.
3-Benzoyl-5-ethyl-4-(fluoromethyl)-4-hydroxy-5-phenyloxazolidin-2-one 8f. Yellow solid (105 mg,
82% yield) after purification by flash chromatography (n-Hexane/EtOAc: 85/15). IR (KBr): 3491, 1802,
1
1678, 1244, 722 cm-1; H NMR (400 MHz, CDCl3): δ = 7.79-7.77 (m, 2H, major), 7.72-7.70 (m, 2H,
minor), 7.65-7.58 (m, 1H, major+minor), 7.50-7.42 (m, 7H, major+minor), 5.68 (d, J= 1.8 Hz, 1H, CH-
Ph, major), 5.56 (s, 1H, CH-Ph, minor), 4.89 (dd, JH-F = 47.3 Hz, J= 10.5 Hz, 1H, CH2F, major), 4.85
(br, 1H, OH, minor), 4.65 (ddd, JH-F = 46.3 Hz, J= 10.0 Hz, J= 0.7 Hz, 1H, CH2F, minor), 4.46 (br, 1H,
OH, major), 4.42 (dd, JH-F= 46.2 Hz, J= 10.5 Hz, 1H, CH2F, major), 4.12 (dd, JH-F= 45.5 Hz, J= 10.0

Hz, 1H, CH2F, minor) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 173.0 (C=O, Bz, major), 172.4 (C=O,
Bz, minor), 152.2 (C=O, major), 151.6 (C=O, minor), 134.0 (CH, Bz, major), 133.3 (CH, Bz, minor),
132.5 (Cq, Bz, minor), 132.1 (Cq, Bz, major), 130.13 (Cq, Ph, major), 130.07 (Cq, Ph, minor), 129.84
(2CH, Bz, major), 129.82 (CH, Ph, major), 129.6 (CH, Ph, minor), 129.2 (2CH, Bz, minor), 128.7 (2CH,
Ph, minor), 128.4 (2CH, Ph, major), 128.3 (2CH, Bz, major), 128.2 (2CH, Bz, minor), 127.9 (2CH, Ph,
major), 126.4 (d, J= 1.6 Hz, 2CH, Ph, minor), 90.3 (d, J= 19.7 Hz, Cq, COH, minor), 89.1 (d, J= 18.2
Hz, Cq, COH, major), 84.5 (d, J= 0.8 Hz, CH-Ph, minor), 80.2 (d, J= 1.6 Hz, CH-Ph, major), 79.1 (d,
J= 181.1 Hz, CH2F, minor), 78.3 (d, J= 183.0 Hz, CH2F, major) ppm; 19F NMR (376.4 MHz, CDCl3): δ
= -221.2 (ddd, J=47.3 Hz, J=46.2 Hz, J=2.4 Hz, 89 %), -223.7 (t, J=45.8 Hz 11 %) ppm; HRMS m/z
(ESI) positive ion, calculated for C17H14FKNO4: [M+K]+ 354.0544, Found: 354.0548.
3-benzoyl-5-(3-bromophenyl)-4-(fluoromethyl)-4-hydroxyoxazolidin-2-one 8g. Yellow solid (95
mg, 90% yield) after purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3434,
1785, 1683, 1245, 723 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.80-7.77 (m, 2H, major), 7.72-7.70 (m,
2H, minor), 7.67-7.57 (m, 3H, major+minor), 7.51-7.47 (m, 2H, major+minor), 7.41-7.37 (m, 1H,
major+minor), 7.36-7.30 (m, 1H, major+minor), 5.63 (d, J= 2.0 Hz, 1H, CH-Ph, major), 5.53 (s, 1H,
CH-Ph, minor), 4.91 (dd, JH-F = 47.2 Hz, J= 10.6 Hz, 1H, CH2F, major), 4.82 (br, 1H, OH, minor), 4.70
(ddd, JH-F = 46.3 Hz, J= 10.2 Hz, J= 0.8 Hz, 1H, CH2F, minor), 4.52 (t, JH-F = 1.4 Hz, 1H, OH, major),
4.43 (dd, JH-F= 46.2 Hz, J= 10.6 Hz, 1H, CH2F, major), 4.15 (dd, JH-F= 45.6 Hz, J= 10.1 Hz, 1H, CH2F,
minor) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 173.0 (C=O, Bz, major), 172.4 (C=O, Bz, minor), 151.9
(C=O, major), 151.1 (C=O, minor), 134.1 (CH, Bz, major), 133.4 (CH, Bz, minor), 132.9 (CH, Ph,
major), 132.8 (CH, Ph, minor), 132.52 (Cq, major), 132.48 (Cq, minor), 132.4 (Cq, minor), 132.0 (Cq,
major), 131.0 (CH, Ph, major), 130.3 (CH, Ph, minor), 129.93 (CH, Ph, major), 129.89 (2CH, Bz,
major), 129.5 (CH, Ph, minor), 129.1 (2CH, Bz, minor), 128.4 (2CH, Bz, major), 128.2 (2CH, Bz,
minor), 126.5 (CH, Ph, major), 125.1 (d, J= 1.6 Hz, CH, Ph, minor), 122.9 (Cq, CBr, minor), 122.6 (Cq,
CBr, major), 90.3 (d, J= 19.8 Hz, Cq, COH, minor), 89.1 (d, J= 18.3 Hz, Cq, COH, major), 83.5 (CH-
Ph, minor), 79.3 (d, J= 1.9 Hz, CH-Ph, major), 79.0 (d, J= 181.4 Hz, CH2F, minor), 78.4 (dd, J= 182.3
Hz, J= 1.4 Hz, CH2F, major) ppm; 19F NMR (376.4 MHz, CDCl3): δ = -221.1 (dddd, J=47.3 Hz, J=46.2
Hz, J=2.2 Hz, J=1.4 Hz, 82 %), -223.7 (t, J=46.0 Hz 18 %) ppm; HRMS m/z (ESI) positive ion,
calculated for C17H13BrFKNO4: [M+K]+ 431.9649, Found: 431.9651.

3-Benzoyl-5-(4-chlorophenyl)-4-(fluoromethyl)-4-hydroxyoxazolidin-2-one 8h. Oil (105 mg, 88%
yield) after purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3447, 1802, 1687,
1156, 696 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.81-7.77 (m, 2H, major), 7.72-7.69 (m, 2H, minor),
7.67-7.66 (m, 1H, major+minor), 7.51-7.38 (m, 6H, major+minor), 5.65 (d, J= 2.3 Hz, 1H, CH-Ph,
major), 5.54 (s, 1H, CH-Ph, minor), 4.90 (dd, JH-F = 47.2 Hz, J= 10.6 Hz, 1H, CH2F, major), 4.81 (br,
1H, OH, minor), 4.69 (ddd, JH-F = 46.3 Hz, J= 10.1 Hz, J= 0.7 Hz, 1H, CH2F, minor), 4.50 (br, 1H, OH,
major), 4.40 (dd, JH-F= 46.3 Hz, J= 10.6 Hz, 1H, CH2F, major), 4.12 (dd, JH-F= 45.6 Hz, J= 10.1 Hz, 1H,
CH2F, minor) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 173.0 (C=O, Bz, major), 172.4 (C=O, Bz, minor),
152.0 (C=O, major), 151.2 (C=O, minor), 136.0 (C-Cl, major), 135.7 (C-Cl, minor), 134.1 (CH, Bz,
major), 133.3 (CH, Bz, minor), 132.4 (Cq, Bz, minor), 132.0 (Cq, Bz, major), 130.18 (Cq, Ph, major),
130.14 (Cq, Ph, minor), 129.9 (2CH, Bz, major), 129.4 (2CH, Ph, major), 129.14 (2CH, Bz, minor),
129.05 (2CH, Ph, minor), 128.7 (2CH, Ph, major), 128.4 (2CH, Bz, major), 128.2 (2CH, Bz, minor),
127.9 (d, J= 1.8 Hz, 2CH, Ph, minor), 90. 2(d, J= 19.7 Hz, Cq, COH, minor), 89.0 (d, J= 18.2 Hz, Cq,
COH, major), 83.8 (d, J= 0.8 Hz, CH-Ph, minor), 79.6 (d, J= 1.8 Hz, CH-Ph, major), 79.0 (d, J= 181.3
Hz, CH2F, minor), 78.3 (d, J= 183.3 Hz, CH2F, major) ppm; 19F NMR (376.4 MHz, CDCl3): δ = -221.1
(ddd, J=47.2 Hz, J=46.3 Hz, J=2.3 Hz, 82 %), -223.7 (t, J=45.9 Hz 18 %) ppm; HRMS m/z (ESI)
positive ion, calculated for C17H13ClFKNO4: [M+K]+ 388.0154, Found: 388.0150.
3-Benzoyl-4-(fluoromethyl)-4-hydroxy-5-(naphthalen-1-yl)oxazolidin-2-one 8i. White solid (60
mg, 52% yield) after purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3457,
1792, 1674, 1330, 726 cm-1; 1H NMR (400 MHz, CDCl3): δ = 8.12-7.39 (m, 12H, major+minor), 6.61
(d, J= 2.0 Hz, 1H, CH-Ant, major), 6.38 (s, 1H, CH-Ant, minor), 5.21 (br, 1H, OH, minor), 4.95 (dd, JH-
F = 47.4 Hz, J= 10.7 Hz, 1H, CH2F, major), 4.59 (ddd, JH-F = 46.5 Hz, J= 10.1 Hz, J= 0.7 Hz, 1H, CH2F,
minor), 4.51 (br, 1H, OH, major), 4.50 (dd, JH-F= 46.0 Hz, J= 10.7 Hz, 1H, CH2F, major), 3.96 (dd, JH-
F= 45.4 Hz, J= 10.2 Hz, 1H, CH2F, minor) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 172.8 (C=O, Bz,
major), 172.7 (C=O, Bz, minor), 152.5 (C=O, major), 151.8 (C=O, minor), 133.9 (CH, Bz, major), 133.6
(Cq, Ant, major), 133.5 (Cq, Ant, minor), 133.3 (CH, Bz, minor), 132.7 (Cq, Bz, minor), 132.3 (Cq, Bz,
major), 131.2 (Cq, Ant, major), 131.1 (Cq, Ant, minor), 130.71 (Cq, Ant, major), 130.70 (Cq, Ant,
minor), 130.24 (CH, Ant, major), 130.15 (CH, Ant, minor), 129.92 (CH, Ant, major), 129.85 (CH, Ant,
minor), 129.84 (2CH, Bz, major), 129.4 (CH, Ant, major), 129.2 (2CH, Bz, minor), 129.1 (CH, Ant,
minor), 128.3 (2CH, Bz, major), 128.2 (2CH, Bz, minor), 127.20 (CH, Ant, minor), 127.15 (CH, Ant,

major), 126.1 (CH, Ant, minor), 125.9 (CH, Ant, major), 125.3 (CH, Ant, minor), 125.1 (CH, Ant, major),
122.8 (CH, Ant, minor), 121.8 (d, J= 1.4 Hz, CH, Ant, minor), 90.5 (d, J= 18.8 Hz, Cq, COH, minor),
89.6 (d, J= 18.5 Hz, Cq, COH, major), 81.7 (CH-Ant, minor), 76.7 (d, J= 1.5 Hz, CH-Ant, major), 79.1
(d, J= 182.1 Hz, CH2F, minor), 78.1 (d, J= 182.2 Hz, CH2F, major) ppm; 19F NMR (376.4 MHz, CDCl3):
δ = -219.7 (t, J=46.0 Hz 40 %), -220.8 (ddd, J=47.5 Hz, J=45.7 Hz, J=2.1 Hz, 60 %)ppm; HRMS m/z
(ESI) positive ion, calculated for C21H16FKNO4: [M+K]+ 404.0700, Found: 404.0698.
3-Benzoyl-5-ethyl-4-(fluoromethyl)-4-hydroxy-5-methyloxazolidin-2-one 8j. White solid (88 mg,
90% yield) after purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3482, 1757,
1695, 1306, 722 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.72-7.68 (m, 2H, major+minor), 7.62-7.57 (m,
1H, major+minor), 7.47-7.43 (m, 2H, major+minor), 4.89 (dd, JH-F = 46.4 Hz, JH-H = 10.5 Hz, 1H, CH2F,
minor), 4.88 (dd, JH-F = 46.5 Hz, JH-H = 10.5 Hz, 1H, CH2F, major), 4.74 (dd, JH-F = 46.2 Hz, JH-H = 10.5
Hz, 1H, CH2F, minor), 4.68 (dd, JH-F = 46.2 Hz, JH-H = 10.5 Hz, 1H, CH2F, major), 4.57 (br, 1H, OH,
major+minor), 2.11-2.01 (m, 1H, CH2-Me, major+minor), 1.93-1.82 (m, 1H, CH2-Me, major+minor),
1.59 (d, J = 3.1 Hz, 3H, CH3, Et, major), 1.53 (s, 3H, CH3, Et, minor), 1.14 (t, J = 7.4 Hz, 3H, Me,
minor), 1.09 (t, J = 7.5 Hz, 3H, Me, major) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 173.0 (C=O, Bz,
major), 172.9 (C=O, Bz, minor), 152.72 (C=O, major), 151.68 (C=O, minor), 133.56 (CH, Bz, major),
133.52 (CH, Bz, minor), 132.59 (Cq, Bz, minor), 132.57 (Cq, Bz, major), 129.51 (2CH, Bz, major),
129.47 (2CH, Bz, minor), 128.22 (2CH, Bz, major), 128.20 (2CH, Bz, minor), 90.5 (d, J= 19.6 Hz, Cq,
COH, minor), 90.4 (d, J= 18.7 Hz, Cq, COH,major), 87.6 (d, J= 1.0 Hz, Cq, CMeEt, minor), 87.1 (d, J=
1.2 Hz, Cq, CMeEt, major), 80.3 (d, J= 183.6 Hz, CH2F, major), 80.2 (d, J= 182.1 Hz, CH2 F, minor),
27.9 (d, J= 4.5 Hz, CH2Me, minor), 27.4 (CH2Me, major), 19.6 (d, J= 5.4 Hz, CH3, Me, major), 17.5
(CH3, Me, minor), 8.1 (CH3, Et, major), 7.9 (d, J= 1.3 Hz, CH3, Et, minor) ppm; 19F NMR (376.4 MHz,
CDCl3): δ = -220.4 (tq, J=46.4 Hz, J=3.0 Hz, 58%), -222.4 (tt, J=46.3 Hz, J=2.2 Hz, 42%) ppm; HRMS
m/z (ESI) positive ion, calculated for C13H14FKNO4: [M+K]+ 320.0700, Found: 320.0702.
(8R,9S,13S,14S)-3’-benzoyl-4’-(fluoromethyl)-4’-hydoxy-10,13-dimethyl-
1,6,7,8,9,10,11,12,13,14,15,16-dodecahydrospiro[cyclopenta[a]phenanthrene-17,5’-
oxazolidine]-2’,3(2H)-dione 8k and (8R,9S,10R,13S,14S)-17-(2-fluoroacetyl)-10,13-dimethyl-3-
oxo-2,3,6,7,8,9,10,11,12,13,14,15,16,17-tetradecadydro-1H-cyclopenta[a]phenanthren-17-yl
benzoylcarbamate 9k (8k:9k = 5:95). White solid (69 mg, 66% yield) after purification by flash

chromatography (n-Hexane/EtOAc: 70/30). IR (KBr): 3420, 3323, 1775, 1678, 1510, 1209, 722 cm-1;
1H NMR (400 MHz, CDCl3): δ = 8.60 (br, 1H, NH, major), 7.87-7.84 (m, 2H, Bz, major+minor), 7.65-
7.60 (m, 1H, Bz, major+minor), 7.53-7.49 (m, 2H, Bz, major), 7.47-7.43 (m, 2H, Bz, minor), 5.87 (s,
1H, minor), 5.72 (d, J = 1.0 Hz, 1H, major), 5.13 (dd, JH-F = 47.2 Hz, JH-H = 15.6 Hz, 1H, CH2F major),
4.93 (dd, JH-F = 46.8 Hz, JH-H = 15.6 Hz, 1H, CH2F major), 4.90 (dd, JH-F = 46.1 Hz, JH-H = 10.3 Hz, 1H,
CH2F minor), 4.77 (dd, JH-F = 47.1 Hz, JH-H = 10.3 Hz, 1H, CH2F minor), 2.90-2.81 (m, 1H, CH2,
major+minor), 2.45-2.26 (m, 4H, CH2, major+minor), 2.00-1.78 (m, 5H, major+minor), 1.72-1.60 (m,
4H, major+minor), 1.52-1.40 (m, 3H, major+minor), 1.19 (s, 3H, CH3, major), 1.15 (s, 3H, CH3, major),
1.26-1.04 (m, 1H, major+minor) 0.93-086 (m, 1H major+minor) ppm; 13C NMR (100.6 MHz, CDCl3): δ
= 203.6 (d, J= 15.1 Hz, C=O, major), 199.5 (C=O, minor), 199.3 (C=O, major), 170.8 (Cq, minor),
170.5 (Cq, major), 164.5 (C=O, Bz, major+minor), 152.2 (C=O, major), 133.4 (CH, Bz, major), 133.0
(CH, Bz, minor), 132.7 (Cq, Bz, minor), 132.5 (Cq, Bz, major), 129.0 (2CH, Bz, major), 128.9 (2CH,
Bz, minor), 128.1 (2CH, Bz, minor), 127.8 (2CH, Bz, major), 124.1 (CH, major), 123.9 (CH, minor),
97.1 (d, J= 0.9 Hz, Cq, major), 84.8 (d, J= 184.8 Hz, CH2, major), 81.5 (d, J= 185.3 Hz, CH2, minor),
52.82 (CH, minor), 52.76 (CH, major), 49.0 (Cq, minor), 48.3 (Cq, major), 47.6 (CH, minor), 47.3 (CH,
major), 38.6 (Cq, minor), 38.4 (Cq, major), 36.3 (CH, minor), 35.7 (CH2, minor), 35.62 (CH, major),
35.59 (CH2, major), 33.9 (CH2, minor), 33.8 (CH2, major), 33.6 (CH2, major+minor), 33.20 (CH2, minor),
33.18 (d, J= 1.1 Hz, CH2, major), 32.7 (CH2, minor), 32.6 (CH2, major), 31.5 (CH2, minor), 31.4 (CH2,
major), 24.5 (CH2, major), 23.4 (CH2, minor), 20.9 (CH2, minor), 20.6 (CH2, major), 17.5 (CH3, minor),
17.4 (CH3, major), 16.3 (CH3, minor), 15.0 (CH3, major) ppm; 19F NMR (376.4 MHz, CDCl3): δ = -223.8
(t, J=46.9 Hz, 5%), -231.3 (t, J=47.0 Hz, 95%) ppm; HRMS m/z (ESI) positive ion, calculated for major
C29H34FKNO5: [M+K]+ 534.2058, Found: 534.2055;
(E)-3-Benzoyl-4-(fluoromethyl)-4-hydoxy-5-(pent-1-en-1-yl)oxazolidin-2-one 8l. White solid (45
mg, 96% yield) after purification by flash chromatography (n-Hexane/EtOAc: 80/20). IR (KBr): 3452,
1
1790, 1673, 1417, 1170, 723 cm-1; H NMR (400 MHz, CDCl3): δ = 7.76-7.73 (m, 2H, major), 7.70-
7.68 (m, 2H, minor), 7.63-7.59 (m, 1H, major+minor), 7.48-7.43 (m, 2H, major+minor), 6.08-6.01 (m,
1H, major+minor), 5.74-5.67 (m, 1H, major+minor), 4.98 (dd, JH-H = 8.8 Hz, JH-F = 2.3 Hz, 1H, CH2F,
major), 4.94 (dd, JH-F = 46.0 Hz, JH-H = 10.1 Hz, 1H, CH2F, minor), 4.84 (dd, JH-F = 47.3 Hz, JH-H = 10.3
Hz, 1H, CH2F, major), 4.66 (br, 1H, OH, minor), 4.57 (dd, JH-F = 45.4 Hz, JH-H = 10.1 Hz, 1H, CH2F,
minor), 4.48(br, 1H, OH, major), 4.30 (dd, JH-F = 46.0 Hz, JH-H = 10.3 Hz, 1H, CH2F, major), 2.19-213

(m, 2H, CH2, major+minor), 1.53-1.44 (m, 2H, CH2, major+minor), 0.95 (t, J = 7.4 Hz, 3H, Me, minor),
0.94 (t, J = 7.4 Hz, 3H, Me, major) ppm; 13C NMR (100.6 MHz, CDCl3): δ = 173.1 (C=O, Bz, major),
172.8 (C=O, Bz, minor), 152.1 (C=O, major), 151.7 (C=O, minor), 142.2 (CH, major), 141.5 (CH,
minor), 133.9 (CH, Bz, major), 133.4 (CH, Bz, minor), 133.2 (Cq, Bz, minor), 132.3 (Cq, Bz, major),
129.8 (2CH, Bz, major), 129.4 (2CH, Bz, minor), 128.3 (2CH, Bz, major), 128.1 (2CH, Bz, minor),
120.9 (d, J = 4.4 Hz, CH, minor), 119.4 (CH, major), 89.4 (d, J= 19.4 Hz, Cq, COH, minor), 89.0 (d, J=
18.3 Hz, Cq, COH, major), 85.2 (d, J= 1.2 Hz, CH, minor), 80.5 (d, J= 1.4 Hz, CH, major), 79.3 (d, J=
181.5 Hz, CH2F, minor), 78.1 (d, J= 181.6 Hz, CH2 F, major), 34.4 (CH2, major), 34.3 (CH2, minor),
21.8 (CH2, minor), 21.7 (CH2, major), 13.57 (CH3, minor), 13.55 (CH3, major) ppm; 19F NMR (376.4
MHz, CDCl3): δ = -221.5 (ddd, J=46.8 Hz, J=46.6 Hz, J=2.9 Hz, 85%), -222.0 (td, J=46.1 Hz, J=3.4
Hz, 15%) ppm; HRMS m/z (ESI) positive ion, calculated for C16H18FKNO4: [M+K]+ 346.0857, Found:
346.0856.
trans-3-benzoyl-4-propyl-5-prop-2-yn-1-yl-1,3-oxazolidin-2-one 10. Oil (38 mg, 35% yield) after
purification by flash chromatography (n-Hexane/EtOAc: 95/5). IR (KBr): 3285, 2125, 1790, 1687, 1375
cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.68-7.65 (m, 2H, Bz), 7.56-7.52 (m, 1H, Bz), 7.44-7.52 (m, 2H,
Bz), 4.57 (dt, J = 7.5 Hz, J = 5.4 Hz, 1H, CH), 4.35 (dt, J = 5.9 Hz, J = 2.9 Hz, 1H, CH), 2.96 (ddd, J =
17.2 Hz, J = 6.3 Hz, J = 2.7 Hz, 1H, CH2), 2.67 (dt, J = 17.2 Hz, J = 2.7 Hz, 1H, CH2), 2.13 (t, J = 2.7
Hz, 1H, Csp-H), 1.85-1.70 (m, 2H, CH2), 1.63-1.46 (m, 2H, CH2), 1.01 (t, J = 7.3 Hz, 3H, CH3) ppm; 13C
NMR (100.6 MHz, CDCl3): δ = 170.1 (C=O, Bz), 152.7(C=O, Bz), 133.2 (Cq, Bz), 132.5 (CH, Bz),
129.1 (2CH, Bz), 127.9 (2CH, Bz), 78.2 (CH), 77.7 (Csp-q), 72.6 (Csp-H), 57.8 (CH), 36.6 (CH2), 21.6
(CH2), 17.9 (CH2), 13.7 (CH3) ppm; HRMS m/z (ESI) positive ion, calculated for C16H17KNO3: [M+K]+
310.0846, Found: 310.0843.
1-((3-(Trifluoromethyl)phenyl)ethynyl)cyclohexyl) tosyl-
2-azanecarboxylate 11. White solid (419
mg, 79% yield) after purification by flash chromatography (n-Hexane/EtOAc: 85/15). IR (KBr): 3355,
3261, 2358, 1753, 700 cm-1; 1H NMR (400 MHz, CDCl3): δ =7.82-7.79 (m, 2H), 7.68-7.67 (m, 1H),
7.60-7.54 (m, 2H), 7.44.7.40 (m, 1H), 7.29-7.27 (m, 2H), 5.13 (br, 1H, NH), 2.41 (s, 3H, Ts-CH3), 2.03-
2.00 (m, 2H, CH2), 1.78-1.56 (m, 8H, CH2), 1.34-1.27 (m, 2H, CH2) ppm; 13C NMR (100.6 MHz, CDCl3):
δ = 150.5 (C=O), 143.5 (Cq, Tos), 139.2 (Cq, Tos), 134.8 (q, J = 1.2 Hz, CH), 130.9 (q, J = 32.3 Hz,
C-CF3), 129.7 (2CH, Tos), 128.8 (2CH, Tos), 128.7 (Cq), 128.5 (q, J = 3.8 Hz, CH), 126.4 (CH), 124.8

(q, J = 3.8 Hz, CH), 123.7 (q, J = 272.2 Hz, CF3), 94.5 (Cq), 82.9 (Cq), 69.2 (Cq), 39.9 (2CH2), 25.2
(CH2), 23.4 (2CH2), 21.5 (Ts-CH3) ppm; HRMS m/z (ESI) positive ion, calculated for C23H22KF3NO4S:
[M+K]+ 504.0859, Found: 504.0860.
(E)-3-tosyl-4-(3-(trifluoromethyl)benzilidene)-1-oxa-3-azaspiro[4.5]decan-2-one 12. White solid
(113 mg, 71% yield) after purification by flash chromatography (n-Hexane/EtOAc: 85/15). IR (KBr):
3229, 1790, 1333, 700 cm-1; 1H NMR (400 MHz, CDCl3): δ =7.64-7.37 (m, 6H), 7.24-7.22 (m, 2H), 6.05
(s, 1H, =CH), 2.41 (s, 3H, Ts-CH3), 1.76-1.50 (m, 8H, CH2), 0.92-0.82 (m, 2H, CH2) ppm; 13C NMR
(100.6 MHz, CDCl3): δ = 152.3 (C=O), 145.9 (Cq, Tos), 138.6 (Cq), 136.5 (Cq), 134.5 (Cq, Tos), 131.8
(CH), 130.7 (q, J = 32.4 Hz, C-CF3), 129.5 (2CH, Tos), 128.8 (q, J = 1.2 Hz, CH), 128.7 (2CH, Tos),
125.2 (q, J = 3.8 Hz, CH), 124.1 (q, J = 3.8 Hz, CH), 124.0 (q, J = 272.5 Hz, CF3 ), 111.5 (CH), 87.6
(Cq), 35.6 (2CH2), 24.6 (2CH2), 21.72 (Ts-CH3), 21.67 (CH2) ppm; HRMS m/z (ESI) positive ion,
calculated for C23H22KF3NO4S: [M+K]+ 504.0859, Found: 504.0857.
4-(fluoro(3-(trifluoromethyl)phenyl)methyl)-4-hydroxy-3-tosyl-1-oxa-3-azaspiro[4.5]decan-2-
one 13. Reaction gave a complex mixture of inseparable compounds that has been analyzed both
with high-resolution mass spectrometry and 13C, 19F, 1H -NMR. Data gave us evidence of the presence
in the mixture of compound 13. The mixture, analyzed with MALDI-TOF HR-Mass spectrometry, gave,
for compound 13, two peak corresponding at [M+Na]+ and at [M+K]+ with the same isotopic profile of
the calculated one for the same molecular formula (see Supporting Information). Moreover, we found,
in 13C-NMR, characteristic doublet of CHF at 91.6 ppm with JC-F = 187.6 Hz and characteristic doublets
1
in19F-NMR at -187.8 ppm and in H- NMR at 5.73 sharing the same coupling constant of JH-F = 43.0
Hz.
4-fluoro-3-oxobutyl tosylcarbamate 18. White solid (46 mg, 82% yield) after purification by flash
chromatography (n-Hexane/EtOAc: 60/40). IR (KBr): 3359, 3261, 1739, 1310, 672 cm-1; 1H NMR (400
MHz, CDCl3): δ = 7.89-7.87 (m, 2H, Tos), 7.34-7.32 (m, 2H, Tos), 5.28 (br, 2H, NH), 4.79 (d, JH-F
=
47.3 Hz, 2H, CH2F), 4.37 (d, J = 6.0 Hz, 2H, CH2), 2.84 (d, J = 6.0 Hz, 2H, CH2), 2.44 (s, 3H, Me, Tos)
ppm; 13C NMR (100.6 MHz, CDCl3): δ = 204.0 (d, J = 19.9 Hz, C=O), 150.5 (C=O), 145.2 (Cq, Tos),
135.4 (Cq, Tos), 129.7 (2CH, Tos), 128.3 (2CH, Tos), 85.0 (d, J = 184.5 Hz, CH2F), 60.5 (CH2), 37.1