Reaction of allenylphosphonates/allenylphosphine oxides with thiocyanates/isothiocyanates or oxalyl chloride/AgNO3

Article abstract of DOI:10.1080/10426507.2017.1287707

In this paper, we describe thiocyanation as well as chlorination of selected allenylphosphonates/allenyl phosphine oxide, using ammonium thiocaynate or (OCH₂CMe₂CH₂O)PNCS (for thiocyanation) or oxalyl chloride/AgNO₃

Full text of DOI:10.1080/10426507.2017.1287707

Phosphorus, Sulfur, and Silicon and the Related Elements
ISSN: 1042-6507 (Print) 1563-5325 (Online) Journal homepage: http://www.tandfonline.com/loi/gpss20
Reaction of allenylphosphonates/allenylphosphine
oxides with thiocyanates/isothiocyanates or oxalyl
Chloride/AgNo3
K. C. Kumara Swamy, Manab Chakravarty, Shubham Debnath & M.
Nagarjuna Reddy
To cite this article: K. C. Kumara Swamy, Manab Chakravarty, Shubham Debnath & M. Nagarjuna
Reddy (2017): Reaction of allenylphosphonates/allenylphosphine oxides with thiocyanates/
isothiocyanates or oxalyl Chloride/AgNo3, Phosphorus, Sulfur, and Silicon and the Related
Elements, DOI: 10.1080/10426507.2017.1287707
To link to this article: http://dx.doi.org/10.1080/10426507.2017.1287707
Accepted author version posted online: 13
Feb 2017.
Submit your article to this journal
View related articles
View Crossmark data
Full Terms & Conditions of access and use can be found at
http://www.tandfonline.com/action/journalInformation?journalCode=gpss20
Download by: [Eastern Michigan University]
Date: 13 February 2017, At: 22:38

ACCEPTED MANUSCRIPT
REACTION OF ALLENYLPHOSPHONATES/ALLENYLPHOSPHINE OXIDES WITH
THIOCYANATES/ISOTHIOCYANATES OR OXALYL CHLORIDE/AgNO3
K. C. Kumara Swamya,*, Manab Chakravartya,b, Shubham Debnatha and M. Nagarjuna Reddya
aSchool of Chemistry, University of Hyderabad, Hyderabad- 500046, Telangana, India
bCurrent address: Department of Chemistry, Birla Institute of Technology & Science, Pilani
Hyderabad Campus, Jawahar Nagar, Shameerpet Mandal, Hyderabad 500 078, Telangana, India
*Corresponding Author E-Mail: kckssc@uohyd.ac.in
Abstract
In this paper, we describe thiocyanation as well as chlorination of selected
allenylphosphonates/allenyl
phosphine
oxide,
using
ammonium
thiocaynate
or
(OCH2CMe2CH2O)PNCS (for thiocyanation) or oxalyl chloride/AgNO3 for chlorination. The
resulting products are vinyl (thiocyanato)phosphonates or vicinal dichloro(vinyl) phosphonates.
One of the vinyl thiocyanato-phosphonates is characterized by single crystal X-ray
crystallography.
Keywords
Allenes; Allenylphosphonates; Allenylphosphine oxides; vinyl thiocyanato-phosphonate, vicinal
dichloro vinylphosphonates
Dedication: This paper is dedicated to Prof. Harry R. Hudson in recognition of his contributions
to phosphorus chemistry
1
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
INTRODUCTION
Allenylphosphonates can be utilized as versatile intermediates in organic synthesis for
diverse transformations owing to their ready availability, stability and low cost of preparation.1 A
variety of substituted vinylphosphonates and allylphosphonates, -keto- and -amino-
phosphonates and phosphorus substituted heterocycles have been synthesized by starting with
allenylphosphonates/allenylphosphine oxides.1-3 Phosphorus based allenes 1-2 (cf. Chart 1) are
useful substrates to explore the chemistry of non-phosphorylated allenes because of the
feasibility of easy monitoring the progress of the reaction by 31P NMR spectroscopy.4
Halogenation/pseudohalogenation of allenes can lead to new vinyl substituted products that
could further be functionalized. Direct halogenation of phosphorus-based allenes using
chlorine/bromine/iodine has been known, but not exhaustively.5-6 Using AgNO3/(COCl)2,
Vankar and co-workers described a simple method for the chloroamidation of olefins.7 Whether
similar reaction occurs with phosphorus-based allenes or not is one of interests in this work. As
regards ‘pseudohalogenation’, a few reports of azidation have been documented.8-9 A couple of
interesting reports on azidation from our group are shown in Scheme 1.8-9 To our knowledge,
studies to incorporate other pseudohaogens appear rather nonexistent. In this communication, we
report some results on the thiocyanic acid addition to allenylphosphonates/allenylphosphine
oxides. X-ray structure of one such product is also reported herein. Later, we report the
chlorination that in contrast to the chloroamidation reaction using alkenes, chlorination takes
place when allenylphosphonates are utilized.
RESULTS AND DISCUSSION
2
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
1.
Reaction of Phosphorus-Based Allenes with (OCH2CMe2CH2O)P-NCS (4) or
Ammonium Thiocyanate- Formation of Vinyl Thiocyanatophosphonates
/
Thiocyanatophosphine oxides or -Ketophosphonates
The isothiocyanato phosphite (OCH2CMe2CH2O)PNCS (4) is prepared by reacting 3 with
potassium thiocyanate in acetonitrile (Scheme 2). The nitrogen end, and not the sulfur end, is
connected to phosphorus on the basis of the observation that the X-ray structure of corresponding
8-membered ring compound CH2(6-t-Bu-4-Me-C6H4O)2P-NCS, prepared by a similar method, is
31
known.10 An interesting feature of compound 4 is that in the P NMR spectrum, the 1J(31P-14N)
coupling is observed. It should be noted that in a majority of compounds with P-N bond this
coupling is not observed.
Upon
treating
allenes
5a-c
with
isothiocyanate
4,
we
obtained
the
vinyl(thiocyanato)phosphonates 6a-c. Since the H-phosphonate 7 is also isolated in this reaction,
we believe that adventitious moisture is involved in this reaction. It can be noted that in the
preparation of vinyl azides from the reaction of Me3SiN3 also, a similar observation is made.
What is interesting in the case of our reaction is that while the N-end (isothiocyanate) is
connected to phosphorus in 4, it is the S-end (thiocyanate) that is connected in 6a-c. The
presence of thiocyanate grouping in 6a-c is clearly shown in the IR spectrum [a band at 2157
cm1]. The other groups were also clearly established by multinuclear NMR. The X-ray structure
of compound 6a is shown in Figure 1. In the case of 6b, as expected, both E and Z isomers are
formed (ratio ~ 7/3).
It is likely that the above addition takes place via HSCN resulting from the hydrolysis of
(OCH2CMe2CH2O)PNCS (4) due to the presence of adventitious moisture. As an alternative
3
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
source of HSCN, we chose ammonium thiocyanate (NH4SCN; dried in vacuum for 2 h), in
acetonitrile or tetrahydrofuran medium for the above reaction with 5a. Here, the 31P NMR
spectrum of the reaction mixture showed two peaks at δ 17.7 (55%, compound 6a) and δ 14.3
(45%). The latter peak is due to the -ketophosphonate (OCH2CMe2CH2O)P(O)CH2C(O)CH3
(8) that could arise due to addition of water to 6a.11,12 Potassium thiocyanate did not react with
the allene. The reaction of allene 5b with NH4SCN led to a considerable amount of the -
ketophosphonate (OCH2CMe2CH2O)P(O)CH2C(O)CH2CH3 (9).11 Allene 5c gave better yields
(60%)
of
the
addition
product
6c
along
with
the
-ketophosphonate
(OCH2CMe2CH2O)P(O)CH2C(O)CH(CH3)2 (10).11
In a manner similar to the above, but by using NH4SCN, we have also been able to synthesize
(thiocyanato)vinyl phosphine oxides 12a-c by starting with the allenylphosphine oxides 11a-c
(Scheme 4).11,13 Compound 4 was not effective for the conversion in these cases. Although the
corresponding -keto products were also present, isolation of the required products could be
accomplished readily in the case of 12a-b. In the case of compound 12c, because of the closeness
of the tlc Rf value with the minor product (possibly the -keto product), it could be isolated only
in 70% purity; the yield of the product initially was >50% (NMR evidence).
2.
Reaction of Phosphorus-Based Allenes with Oxalyl Chloride/AgNO3 System
4
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
The basis for attempting this reaction was to have an analogy with that in the literature
between alkenes and AgNO3/oxalyl chloride under similar conditions. Using AgNO3/(COCl)2
Vankar and co-workers described a simple method for the chloroamidation of olefins (Scheme
5).7 In this reaction, acetonitrile acted both as the solvent and as the reagent.
The reaction of allenylphosphonates 13-15 with oxalyl chloride and AgNO3 led to a
mixture of products (16a-c, 17a and 18a-c) (Scheme 5). In these cases, oxalyl chloride acted as a
chlorine source (acetyl chloride failed to react). The reaction involves addition of two chlorine
atoms across double bond of allene to lead to three distinct isomeric products in the reaction
using 13 (cf. Figure 2). Only compounds 16a, 17a, 18a and 18b could be isolated in a pure state.
Thus it should be noted that the reaction of AgNO3/(COCl)2 with allenes proceeds in a manner
different from that with alkenes. The assignment of structures is based on NMR and HRMS data.
1
As an example, compound 16a shows two singlets at δ 5.79 and 6.34 in the H NMR spectrum
corresponding to geminal alkene protons and a doublet for PC carbon at δ 75.5 [1J(PC) = 152.0
Hz] in the 13C NMR spectrum for the P-C(sp3) carbon. Compound 18b shows a singlet at δ 4.05
1
13
in H NMR due to CH2 protons; a doublet at δ 132.4 [1J(PC) = 175.0 Hz] in the C NMR
indicates the presence of P-C = C moiety. The molecular identity (two chlorine patterns) of the
isolated compounds is also confirmed by HRMS data. The basis for the assignment of isomers
16c and 18c stems from literature reports on the reaction of nonphosphorus-allenes with
(COCl)2/ [BnEt3N][MnO4].14 In earlier literature reports on the direct chlorination (by Cl2) of
allenylphosphine oxides heterocyclic phosphonium salt 19 (Scheme 7a) was isolated, but in one
case, vicinal dichlorovinylphosphine oxides were identified (but not isolated) by NMR
spectroscopy.6a In another report, only compound 20 that is analogous to 16b-18b (or 16c-18c)
5
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
were identified (Scheme 7b).6b These products, however, were different from those contemplated
in our initial objective.
CONCLUSIONS
In this preliminary report, we have shown that allenylphosphonates react with
isothiocyanato substituted phosphites to lead to vinyl(thiocyanato)phosphonates. Such
vinyl(thiocyanato)phosphonates may also be prepared directly by the reaction of allenes with
ammonium thiocyanate. The yields are moderate, but the products could be synthetically
valuable in view of the reactive thiocyanate and alkene moiety. This reaction appears to occur in
the presence of adventitious moisture in a manner similar to that with trimethylsilyl azide. The
structure of one such thiocyanato compound has been confirmed by single crystal X-ray
crystallography. However, a competitive reaction leading to -ketophosphonates is also formed,
depending on the allenylphosphonate/allenylphosphine oxide used.
In contrast to the reaction of AgNO3/oxalyl chloride with normal olefins wherein
chloroamidation occurs,7 the analogous reaction with allenes give only vicinal dichloro
vinylphosphonates. Many such vicinal (dichloro)vinylphosphonates have been isolated and
characterized in the present study.
Experimental Section
Chemicals were purified when required according to standard procedures.15 All reactions, unless
1
13
31
stated otherwise, were performed in a dry nitrogen atmosphere. H, C and P NMR spectra
were recorded using 5 mm tubes on 200, 400 or on 500 MHz spectrometer with field strengths
200/50/80, 400/100/160 or 500/125/202 MHz, respectively in CDCl3 solution with shifts
6
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
referenced to SiMe4 or ext. 85% H3PO4 ( = 0). All J values are in Hz. Infrared spectra were
recorded neat or by using KBr pellets on a FT/IR spectrometer. Melting points were determined
by using a local hot-stage melting point apparatus and are uncorrected. For TLC, glass micro
slides were coated with silica-gel-GF254 (mesh size 75) and spots were identified using iodine
or UV chamber as appropriate. For column chromatography, silica gel of 100-200 mesh size was
used. Mass spectra were recorded using HRMS (ESI-TOF analyzer) equipment. Details of
spectra are available with the authors.
(i) Synthesis of the isothiocyanate compound 4
16
The precursor (OCH2CMe2CH2O)PCl (3) (3.58 g, 16.0 mmol) was stirred with potassium
thiocyanate (4.6 g, 48.0 mmol) in dry acetonitrile for 4 d at room temperature (25 C). Then, the
solvent was removed under vacuum; the required compound 4 was extracted with dry hexane
1
and purified by vacuum distillation. Yield: Quantitative. Bp: 80-90 oC (16 mm Hg). H NMR
(400 MHz): δ 0.81 and 1.24 (2 s, 6 H, CH(CH3)2), 3.55 (dd  t, J(PH) ~ J(HH) ~10.5 Hz each, 2
13
H, -OCH2), 4.11 (dd  t, J(PH) ~ J(HH) ~10.5 Hz each, 2 H, OCH2). C NMR (50 MHz):δ
22.3, and 22.6 (2 s, CH(CH3)2), 32.9 (d, J(PC) = 4.0 Hz, CMe2), 72.0 (br, OCH2), 146.8 (br, -
31
NCS). P NMR (80 MHz): δ 105.5 (t, J(PN) ~ 66.0 Hz). LCMS: m/z 191. This compound was
hydrolytically unstable.
(ii) Reaction of 5a with 4: Preparation of (OCH2CMe2CH2O)P(O)CH2C(SCN) = CH2 (6a)
To a solution of 5a (0.20 g, 1.06 mmol) in dry THF (OCH2CMe2CH2O)PNCS (4) (0.40 g,
2.12 mmol) was added via syringe. The reaction mixture was heated under reflux for 24-48 h.
7
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
The reaction mixture 31P NMR showed mainly two peaks: one at δ 17.9 (product) and the second
at δ 1.1 that corresponded to (OCH2CMe2CH2O)P(O)H. The reaction mixture was washed with
water (350 mL) and extracted with ether (325 mL). After the removal of solvent from the
extract, and subjecting the residue to column chromatography (EtOAc/hexane 1/1; silica gel)
afforded 6a that was then crystallized from CH2Cl2-hexane (1:1) mixture. Yield: 0.21 g (80%).
1
Mp:108-110 C. IR (KBr): 2159, 1618, 1476, 1261, 1055, 1007 cm1. H NMR (200 MHz): δ
1.07 and 1.13 (2 s, 6 H, C(CH3)2)), 3.05 (d, J(PH) = 21.1 Hz, 2 H, PCH2), 3.93 (dd  t, J(PH) ~
J(HH)~12.0 Hz each, 2 H, OCH2), 4.24 (dd  t, J(PH) ~ J(HH) ~ 12.0 Hz each, 2 H, OCH2),
5.80-5.83 (m, 2 H, = CH2). 13C NMR (50 MHz): δ 21.4 and 21.5 (2 s, C(CH3)2), 32.3 (d, J(PC) =
134.9 Hz, PCH2), 32.6 (d, J(PC) = 6.5 Hz, C(CH3)2), 75.9 (d, J(PC) = 6.0 Hz, OCH2), 109.5 (s,
SCN), 124.3 (d, J(PC) = 9.9 Hz, = CH2), 124.7 (d, J(PC) = 11.2 Hz, PC-C). 31P NMR (80 MHz):
δ 17.6. Anal. Calcd. for C9H14O3PNS: C, 43.72; H, 5.70; N, 5.66; S, 12.97. Found: C, 43.70; H,
5.70; N, 5.74; S, 12.88. X-ray structure was determined for this sample.
(iii) Preparation of (OCH2CMe2CH2O)P(O)CH2C(SCN) = CH(Me) (6b- isomeric mixture)
This compound was prepared as a mixture of isomers (E:Z = 7:3) using a procedure
similar to that for 6a using 5b with the same molar quantities of reactants. Yield: 0.13 g (50%).
Mp: 72-74 C. IR (KBr): 2157, 1478, 1263, 1057, 1005 cm1. 1H NMR (200 MHz, major isomer,
ca 85%): δ 1.05 and 1.11 (2 s, 6 H, C(CH3)2)), 1.94--1.96 (m, 3 H, = C(CH3), 3.10 (d, J(PH) =
20.5 Hz, 2 H, PCH2), 3.89-3.95 (m, 2 H, OCH2), 4.20--4.25 (m, 2 H, OCH2), 6.32--6.35 (m, 1 H,
= CH). 13C NMR (50 MHz): δ 16.4 (s, = C(CH3)), 21.4 and 21.5 (2 s, C(CH3)2), 32.6 (br,
C(CH3)2), 33.5 (d, J(PC) = 136.0 Hz, PCH2), 75.7 (d, J(PC) = 6.1 Hz, OCH2), 110.2, 115.6
8
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
(SCN), 139.0 (d, J(PC) = 9.9 Hz). 31P NMR (80 MHz): δ 19.2. For the minor isomer, other peaks
1
(ca~ 15%) at δ 1.03, 1.12, 1.86-1.89 (m), 6.29- 6.30 (m) in the H NMR and a peak at δ 19.4 in
31P NMR spectra were observed. Anal. Calcd. for C10H16O3PNS: C, 45.96; H, 6.17; N, 5.36.
Found: C, 45.94; H, 6.18; N, 5.30.
(iv) Preparation of (OCH2CMe2CH2O)P(O)CH2C(SCN) = CMe2 (6c)
The procedure and molar quantities were the same as that for 6a. Yield: 0.144 g (60%).
Mp: 64-66 C. IR (KBr): 2151, 1680, 1474, 1273, 1061, 1011 cm1. 1H NMR (200 MHz): δ 1.04
and 1.13 (2 s, 6 H, C(CH3)2)), 2.01 and 2.11 (2 d, J(HH) ~ 5.0 Hz each, 6 H, = C(CH3)2), 3.18 (d,
J(PH) = 20.8 Hz, 2 H, PCH2), 3.92 (dd  t, J(PH) ~ J(HH) ~ 11.2 Hz each, 2 H, OCH2), 4.24
(dd  t, J(PH) ~ J(HH) ~11.2 Hz each, 2 H, OCH2). 13C NMR (50 MHz): δ 21.4, 21.5, 22.6 and
22.4 (4 s, C(CH3)2 + = C(CH3)2), 31.3 (d, J(PC) = 138.3 Hz, PCH2), 32.7 (br, C(CH3)2, signals
are merged with PCH2), 75.4 (d, J(PC) = 6.1 Hz, OCH2), 107.6 (d, J(PC) = 14.6 Hz), 110.8
(SCN), 149.0 (d, J(PC) = 10.9 Hz). 31P NMR (80 MHz): δ 20.7. Anal. Calcd. for C11H18O3PNS:
C, 47.99; H, 6.59; N, 5.08; S, 11.64. Found: C, 47.95; H, 6.56; N, 5.16; S, 11.64.
(v) Preparation of Ph2P(O)CH2C(SCN) = CRR’ (12a-c)
A mixture of NH4SCN (2 equiv) and the allenylphosphine oxide (one equiv) was heated under
reflux in THF (ca 1 mL/1 mmol of allene) for 12 h. After removal of the solvent,
dichloromethane (2 mL) was added to the residue and the soluble portion was column
chromatographed (acetone/hexane 1/1; silica gel) to obtain one of 12a-c.
Compound 12a (0.208 mmol of allene 11a [(P) 24.6] was used): Yield: 30 mg (60%), Mp:
114-116 C. IR (KBr): 2926, 2151, 1609, 1433, 1170, 1128, 1092, 1066, 896, 844, 746, 725, 700
9
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
cm1. 1H NMR (500 MHz): δ 3.44 (d, J = 13.0 Hz, 2H, -PCH2), 5.70-5.74 (m, 2H, = CH2), 7.51-
7.54 (m, 4H, Ar-H), 7.77- 7.81 (m, 4H, ArH), 7.58-7.59 (m, 2H, Ar-H). 13C NMR (125 MHz): δ
37.9 (d, J = 52.0 Hz, -PC), 109.9, 124.66, 124.72, 125.16, 125.24, 128.9, 129.0, 130.8, 130.9,
131.0, 131.6, 132.5, 132.5. 31P NMR (202 MHz): δ 27.28. HRMS (ESI): Calcd. for C16H15NOPS
[M++H]: m/z 300.0612. Found: 300.0607.
Compound 12b (0.79 mmol of allene 11b [(P) 25.1] was used): Yield: 83 mg (42%), Mp: 108-
110 C, IR (KBr): 3057, 2916, 2152, 1636, 1590, 1484, 1438, 1403, 1334, 1199, 1120, 998, 951,
833, 743, 722, 696, 565 cm1. 1H NMR (500 MHz): δ 1.71-1.74 (m, 3H, CH3), 3.52 (d, J = 12.5
Hz, 2H, -PCH2), 6.35-6.37 (qrt, 1H, = CH), 7.51-7.54 (m, 4H, ArH), 7.58 (t, J = 10.0 Hz, 2H, Ar-
H), 7.80-784 (m, 4H, Ar-H). The amount of the other possible stereo-isomer was <1%. 13C NMR
(125 MHz): δ 16.0 (d, J = 10.0 Hz, -CH3), 34.4 (d, J = 65.0 Hz, -PC), 111.26 111.27, 115.7,
31
115.8, 128.8, 128.9, 130.91, 131.01, 131.3, 132.28, 132.37, 132.40, 140.1, 140.2. P NMR (202
MHz): δ 26.91. HRMS (ESI): Calcd. for C17H16NOPSNa [M++Na]: m/z 336.0588. Found:
336.0585.
Compound 12c (purity ca 70% only) (0.75 mmol of allene 11c [(P) 27.1] was used): Yield: ca
80 mg (~40% for the expected compound; although initially it was >50%, the yield became
lower during separation), Mp: ~122 C, IR (KBr): 3056, 2915, 2150 (SCN), 1958, 1438, 1197,
1
1120, 794, 737 cm1. H NMR (500 MHz): δ 1.82 and 2.06 (two s, 6H, CH3), 3.60 (d, J = 12.0
Hz, 2H, -PCH2), 7.30-7.83 (m, ca 10 H, ArH). For the minor product, signals were observed at δ
1.55 and 5.68 (br m) in addition to the signals for the aromatic protons. 13C NMR (125 MHz): δ
22.7 (d, J = 2.0 Hz)) and 24.1 (d, J = 2.0 Hz), 36.8 (d, J = 53.0 Hz, -PC), 97.6 (d, J = 19.0 Hz),
10
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
108.2 (d, J = 9.0 Hz), 111.3 (SCN), 128.7 (J = 9.4 Hz), 131.0 (J = 7.4 Hz), 132.5, 149.5 (d, J =
6.8 Hz). Signals for the minor product were observed at 18.8 (d, J = 4.6 Hz, -CH3), 83.6 (J =
85.3 Hz) and 210.9 along with peaks for Ar-C nuclei and hence the full analysis was not made..
31P NMR (202 MHz): δ 27.2 (minor product signal at 26.0). HRMS (ESI): Calcd. for
C18H18NOPSNa [M++H]: m/z 328.0923. Found: 328.0924.
(vi) Synthesis of vicinal dichloro(vinyl)phosphonates 16a, 17a and 18a-b
To a suspension of silver nitrate (1.5 mmol) in dry CH3CN (4 mL) was added oxalyl
chloride (1.5 mmol) drop-wise via syringe at 0 C. After 5 min, one of the allenylphosphonates
13-1511,13 (1.0 mmol) was added and the contents were stirred for 3 h at 0 C. The reaction
mixture was quenched with water (10 mL) and extracted with ethyl acetate (410 mL). The
collected organic layers were washed with brine solution (10 mL), dried over anhydrous Na2SO4,
filtered and concentrated. The residue was subjected to column chromatography to afford the
products 16a, 17a and 18a-b.
Compound 16a: Yield: 0.127 g (38%); Mp: 136-138 C; IR (KBr): 2978, 1822, 1622, 1545,
1
1487, 1261, 1154, 1065, 1022, 901, 829, 710, 542 cm1; H NMR (400 MHz):  0.80 (s, 3H,
CH3), 1.26 (s, 3H, CH3), 4.02-4.20 (m, 4H, 2 OCH2), 5.80 (s, 1H, = CHaHb), 6.36 (s, 1H, =
CHaHb), 7.39-7.44 (m, 3H, Ar-H), 7.69-7.72 (m, 2H, Ar-H). 13C NMR (100 MHz):  20.6, 22.1,
32.8 (d, J = 10 Hz), 75.5 (d, J = 152.0 Hz), 80.0 (dd→t, J = 10.0 Hz), 120.8, 128.2, 128.7, 129.0,
134.2, 138.7 (d, J = 12.0 Hz). 31P NMR (160 MHz):  3.8. HRMS (ESI): Calcd. for
C14H17Cl2NaO3P [M++Na]: m/z 357.0190, 359.0348 and 361.0179. Found: 357.0186, 359.0156
and 361.0121.
11
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Compound 17a: Yield: 0.25 g (70%); Mp: 116-118 C; IR (KBr): 2964, 1825, 1611, 1501,
1
1463, 1255, 1178, 1063, 1025, 910, 822, 762, 537 cm1. H NMR (400 MHz):  0.84 (s, 3H,
CH3), 1.27 (s, 3H, CH3), 3.82 (s, 3H, OCH3), 3.91-4.25 (m, 4H, 2 OCH2), 5.78 (s, 1H, = CHaHb),
6.33 (s, 1H, = CHaHb), 6.92 (d, J = 8.8 Hz, 2H, Ar-H), 7.60 (dd, J = 8.8 and 2.0 Hz, 2H, Ar-H).
13C NMR (100 MHz):  20.6, 22.1, 32.8 (d, J = 8.0 Hz), 55.3, 75.2 (d, J = 153.0 Hz), 79.9
31
(dd→t, J = 10.0 Hz), 113.6, 120.5, 126.0, 130.0, 138.9 (d, J = 10.0 Hz), 160.0. P NMR:  4.1
(160 MHz). HRMS (ESI): Calcd. for C15H20Cl2O4P [M++H]: m/z 365.0477, 367.0635 and
369.0793. Found: 365.0479, 367.0450 and 369.0419.
Compounds 18a and 18b: The separation was done using hexane-ethyl acetate mixture [3:2
ratio for 18a and 2:3 ratio for 18b] as the eluent. 18a: Yield: 0.092 g (25%). Mp: 130-132 C. IR
1
(KBr): 2964, 1825, 1611, 1501, 1463, 1255, 1178, 1063, 1025, 910, 822, 762, 537 cm1. H
NMR (400 MHz):  0.88 (s, 3H, CH3), 1.28 (s, 3H, CH3), 4.02-4.37 (m, 4H, 2 OCH2), 5.79 (s,
13
1H, = CHaHb), 6.34 (s, 1H, = CHaHb), 7.37-7.39 (m, 2H, Ar-H), 7.62-7.64 (m, 2H, Ar-H). C
NMR (100 MHz):  20.7, 22.2, 33.0 (d, J = 10.0 Hz), 75.2 (d, J = 151.0 Hz), 80.2 (dd→t, J ~
10.0 Hz), 121.0, 128.4, 130.2, 132.9, 135.2, 138.4 (d, J = 12.0 Hz). 31P NMR (160 MHz):  3.5.
HRMS (ESI): Calcd. for C14H17Cl3O3P [M++H]: m/z 368.9982, 371.0140, 373.0298 and
375.0456. Found: 368.9983, 370.9952, 372.9928 and 374.9909. 18b: Yield: 0.155 g (42%). Mp:
142-144 C. IR (KBr): 2970, 2882, 1595, 1474, 1267, 1063, 1008, 975, 838, 794, 526 cm1. 1H
NMR (400 MHz):  0.83 (s, 3H, CH3), 1.18 (s, 3H, CH3), 3.68 (dd, J = 11.2 and 6.8 Hz, 2H,
OCH2), 3.92 (dd, J ~ 17.2 and 11.2 Hz, 2H, OCH2), 4.05 (s, 2H, CH2), 7.32 (dd, J ~ 8.8 and 2.0
13
Hz, 2H, Ar-H), 7.41 (d, J = 8.8 Hz, 2H, Ar-H). C NMR (100 MHz):  20.9, 21.7, 32.3 (d, J =
12
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
7.0 Hz), 46.3 (d, J = 14.0 Hz), 76.5, 76.6, 129.3, 130.0 (d, J = 5.0 Hz), 131.5, 132.4 (J = 175.0
Hz), 135.3, 144.1. 31P NMR (160 MHz):  4.4. HRMS (ESI): Calcd. for C14H16Cl3NaO3P
[M++Na]: m/z 390.9801, 392.9959 and 395.0117. Found: 390.9803, 392.9778 and 394.9747.
X-ray data for compound 6a [CCDC: 1524604] was collected at 293 K on a Bruker AXS-
SMART diffractometer using Mo-K radiation ( = 0.71073 Å) using standard methods.17
Copies of the information may be obtained free of charge from The Director, CCDC, 12 Union
Road, Cambridge CB2 1 EZ, UK (Fax: + 44-1223-336033; email: deposit@ccdc.cam.ac.uk or
www.ccdc.can.ac.uk). Crystal data for compound 6a: Emp. formula C9H14NO3PS; Formula
weight 247.24; Crystal system Monoclinic; Space group P2(1)/c; a /Å 6.7093(5); b /Å
17.4433(12); c /Å 11.1154(7); /deg 102.2960(10); V /Å3 1271.02(15); Z = 4; D
calc
/g cm3
1.292;  /mm1 0.369; F(000) 520; Data/ restraints/ parameters 2225 / 0/ 138; S 1.061; R1 [I>2
(I)] 0.0475; wR2 [all data] 0.1334; Max./min. residual electron dens. [eÅ3] 0.195/ - 0.351
ACKNOWLEDGMENTS:
We thank Council of Scientific and Industrial Research (CSIR), Department of Science and
Technology (DST-FIST and PURSE), and University Grants Commission (UGC-UPE-2) for
financial support.
13
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
REFERENCES
1. Selected references: (a) Khusainova, N. G.; Pudovik, A. N. Russ. Chem. Rev. 1987, 56, 564
(review) (b) Alabugin, I. V.; Brel, V. K. Russ. Chem. Rev. 1997, 66, 205 (c) Bhuvan Kumar,
N. N.; Nagarjuna Reddy, M.; Kumara Swamy, K. C. J. Org. Chem. 2009, 74, 5395-5404 (d)
Pavan, M. P.; Reddy, M. N.; Kumar, N. N. B.; Kumara Swamy, K. C. Org. Biomol. Chem.,
2012, 10, 8113-8118 (e) Siva Kumari, A. L.; Srinivas, V.; Kumara Swamy, K. C. J. Chem.
Sci. 2013, 125, 1405-1417 (f) Gangadhararao, G.; Kotikalapudi, R.; Reddy M. N.; Kumara
Swamy K. C. Beilstein J. Org. Chem. 2014, 10, 996-1005 (g) Anitha, M.; Gangadhararao,
G.; Kumara Swamy, K. C. Org. Biomol. Chem. 2016, 14, 3591-3602 (h) Nagaraju, K.;
Kumara Swamy, K. C. Org. Biomol. Chem. 2016, 14, 5079-5087. i) Srinivas, V.; Sajna, K.
V.; Kumara Swamy, K. C. Chem. Commun. 2011, 47, 5629-5631. (j) Sajna, K. V.; Kumara
Swamy, K. C. J. Org. Chem. 2012, 77, 5345-5356.
2. (a) Baumann, M.; Baxendale, I. R. J. Org. Chem. 2015, 80, 10806-10816 (b) Bogachenkov,
A. S.; Dogadina, A. V.; Boyarskava, I. A.; Boyarskiy, V. P.; Vasilyev, A. V. Org. Biomol.
Chem. 2016, 14, 1370-1381 (c) Ye, J.; Ma, S. Acc. Chem. Res. 2014, 47, 989-1000 (d)
Panossian, A.; Fleury-Bregeot, N.; Marinetti, A. Eur. J. Org. Chem. 2008, 3826-3833 (e) He,
G.; Fu, C.; Ma, S. Tetrahedron 2009, 65, 8035-8042 (f) He, G.; Yu, Y.; Fu, C.; Ma, S. Eur. J.
Org. Chem. 2010, 101-110 (g) Pinto, N.; Neel, M.; Panossian, A.; Retailleau, P.; Frison, G.;
Voituriez, A.; Marinetti, A. Chem. Eur. J. 2010, 16, 1033-1045 (h) Xin, N.; Ma, S. Eur. J.
Org. Chem. 2012, 3806-3817 (i) Chen, Y-Z.; Zhang, L.; Lu, A-M.; Yang, F.; Wu, L. J. Org.
Chem. 2015, 80, 673-680 (j) Mazzuca, D.; Angelov, C.; Wiebe, L. I. J. App. Pharm. Sci.
14
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
2015, 5(11), 001-009 (k) Guo, H.; Yu, F.; Ma, S. J. Org. Chem. 2006, 71, 6634-6636 (l) Yu,
F.; Lian, X.; Ma, S. Org. Lett. 2007, 9, 1703-1706.
3. (a) Panossian, A.; Fleury-Bregeot, N.; Marinetti, A. Eur. J. Org. Chem. 2008, 3826. (b) Brel,
V. K.; Belsky,V. K.; Stash, A. I.; Zavodnik, V. E.; Stang. P. J. Org. Biomol. Chem. 2003, 1,
4220 (c) Brel, V. K.; Belsky,V. K.; Stash, A. I.; Zavodnik, V. E.; Stang. P. J. Eur. J. Org.
Chem. 2005, 512 (d) Zhang, M. L.; Chen, Y.-Z.; Zhu, J.; Wu, L. ACS Catal. 2017, 7,
181−185.
4. (a) Sajna, K. V.; Kotikalapudi, R.; Chakravarty, M.; Bhuvan.Kumar, N. N.; Kumara Swamy,
K. C. J. Org. Chem. 2011, 76, 920-938 (b) Chakravarty, M.; Kumara Swamy, K. C. J. Org.
Chem. 2006, 71, 9128-9138 (c) Srinivas, V.; Balaraman, E.; Sajna, K. V.; Kumara Swamy,
K. C. Eur. J. Org. Chem. 2011, 4222-4230.
5. (a) Christov, V. C.; Prodanov, B. Phosphorus, Sulfur Silicon Relat. Elem., 2002, 177, 243–
249 (a) Guo, H.; Qian, R.; Guo, Y.; Ma, S. J. Org. Chem. 2008, 73, 7934-7938 and
references cited therein/(b) Ma, S. Acc. Chem. Res., 2009, 42, 1679–1688 .
6. (a) Angelov, C. M. Phosphorus and Sulfur, 1983, 15, 177-183. (b) Angelov, C. M.
Phosphorus and Sulfur, 1988, 37, 125-128.
7. Rawal, G. K.; Kumar, A.; Tawar, U.; Vankar, Y. D. Org. Lett. 2007, 9, 5171-5174.
8. Chakravarty, M.; Bhuvan Kumar, N. N.; Sajna, K. V.; Kumara Swamy, K. C. Eur. J. Org.
Chem. 2008, 4500–4510.
9. Sajna, K. V.; Kumara Swamy, K. C. J. Org. Chem. 2012, 77, 8712-8722.
10. Kumaraswamy, S.; Senthil Kumar,K.; Satish Kumar, N.; Kumara Swamy, K. C. Dalton
Trans. 2005, 1847-1851.
15
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
11.
Kumar, N. N. B.; Chakravarty, M.; Kumar, N. S.; Sajna, K. V.; Kumara Swamy, K. C. J.
Chem. Sci., 2009, 121, 23-36 and references cited therein.
12. Morita, I.; Chokai, S.; Tsuda, M.; Kise, M.; Sugiyama, M. Chem. Pharm. Bull. 1988, 36,
1135
13. (a) Guillemin, J. C.; Savignac, P.; Denis, J. M. Inorg. Chem. 1991, 30, 2170 and references
cited therein. (b) Sajna, K. V. Cycloaddition/ Cyclization Reactions of Allenylphosphonates/
Related Allenes and Palladium-Catalyzed Diarylation of Alkynes, PhD thesis, University of
Hyderabad, 2011.
14. Boyes, A. L.; Wild, M. Tetrahedron Lett. 1998, 39, 6725.
15. Perrin, D. D.; Armarego, W. L. F.; Perrin, D. Purification of Laboratory Chemicals;
Pergamon: Oxford UK 1986.
16. Kumara Swamy, K. C.; Kumaraswamy, S.; Senthil Kumar, K.; Muthiah, C. Tetrahedron Lett.
2005, 46, 3347-3351.
17. Structure solution and refinement: Sheldrick, G. M. SADABS, Siemens Area Detector
Absorption Correction, University of Göttingen, Germany, 1996. (b) Sheldrick, G. M.,
SHELX-97- A program for crystal structure solution and refinement, University of
Göttingen, Germany, 1997. (c) Sheldrick, G. M. SHELXTL NT Crystal Structure Analysis
Package, Bruker AXS, Analytical X-ray System, WI, USA, 1999, version 5.10.
16
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Figure 1. Molecular structure of compound 6a. Selected bond lengths [Å] with esd’s in
parentheses: C(6)-P 1.789(3), C(6)-C(7) 1.485(4), C(7)-C(8) 1.311(4), C(7)-S 1.783(3), C(9)-S
1.664(4), C(9)-N 1.143(4). Bond angle (o) for S-C(9)-N 177.5(4).
17
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
8
7
6
5
4
3
ppm
Figure 2. 31P NMR spectrum for the reaction mixture resulting from the addition of
(COCl)2/AgNO3 to allene 13.
18
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Scheme 1 Reactivity of vinyl azidophosphonates derived from allenylphosphonates.
19
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Scheme 2 Synthesis of the isothiocyanato compound 4
20
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Scheme 3 Synthesis of the thiocyanato compounds 6a-6c
21
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Scheme 4 Synthesis of the thiocyanato compounds 12a-12c via NH4SCN and allenes 11a-c
22
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Scheme 5 Amidochlorination reaction of cyclohexene using AgNO3/(COCl)2
23
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Scheme 6 Vicinal chlorination of allenylphosphonates using AgNO3/(COCl)2
24
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Scheme 7 Selected literature reports on chlorination of allenylphosphine oxides
25
ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
Chart 1 Phosphorus based allenes 1-2
26
ACCEPTED MANUSCRIPT